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0.017453292519943295: The number of radians in 1 degree.
0.301029995664: log₁₀(2)
0.434294481903: log₁₀(e)
0.477121254720: log₁₀(3)
0.497149872694: log₁₀(π)
0.57721566490: Euler′s constant.
0.693147180560: log_e(2)
0.915965594177219015: Catalans constant.
1.098612288668: log_e(3)
1.414213562: Square root of 2.
1.9021605824: Brun′s constant, the sum of the reciprocals of all twin primes.
2.302585092994: log_e(10)
2.71828: The base of natural (Napierian) logarithms
2D: Having both width and length, but no thickness.
3.14159265: Pi is the number of times the diameter of a circle can be divided into the circumference.
3D: Having length, width, and thickness i.e. space.
57.29577951308232: The number of degrees in 1 radian.
Ab Initio: Latin meaning "from first principles".
Abacus: The uppermost part of a colurnn capital or pilaster, on which the architrave rests. Also, a bead frame used as an arithmetic calculating aid.
Abelian Group: A mathematical group of transformations with the property that the end result of a series of transformations does not depend on the order in which they are performed.
Abscissa: The x coordinate on an (x, y) graph.
Absolute Value: The positive value for a real number, disregarding the sign.
Abundant Number: A positive integer that is smaller than the sum of its proper divisors.
Acute Angle: A positive angle that is less than 90 degrees.
Acute Triangle: A triangle in which all of the angles are less than 90 degrees.
Addition: The operation of finding the sum of two or more quantities.
Addition of Ordinates: A graphing technique where two or more functions are independently plotted on the same graph, then their y-coordinates are added together at each point to form the new graph.
Additive Identity: The additive identity is the number zero, because zero will not change a number when added to it: a + 0 = a for all a.
Additive Inverse: The addition of number and it′s additive inverse is zero. The additive inverse of a number a is -a, also known as the opposite of a, such that a + (-a) = 0. For example, 1 + (-1) = 0.
Adjacent Angles: Two angles are adjacent if they share a common vertex and have a common side between them.
Algebra: First major treatise written by Al-Khawarizmi in AD 810.
Algebraic Equation: An equation of the form f(x)=0 where f is a polynomial.
Algebraic Number: A number that is the root of an algebraic polynomial.
Algorithm: A logical sequence of instructions that explain how to accomplish a task. It must explain exactly how to go from one step to the next and have a finite amount of steps.
Align: To adjust or set to a line or centre.
Alpha: The first letter of the Greek alphabet.
Alphametic: A cryptarithm in which the letters, which represent distinct digits, form related words or meaningful phrases.
Alternate Exterior Angles: Exterior angles on alternate sides of the transversal ie not on the same parallel line.
Alternate Interior Angles: Interior angles on alternate sides of the transversal ie not on the same parallel line.
Altitude of a Conic Solid: The length of a segment whose endpoints are the vertex and a point on the plane of the base that is perpendicular to the plane of the base.
Altitude of a Cylindric Solid: The distance between the planes of the bases.
Altitude of a Trapezoid: The distance between the bases of a trapeziod.
Altitude of a Triangle: The perpendicular segment from a vertex to the line containing the opposite side of a triangle.
Amicable Numbers: Two numbers are said to be amicable if each is equal to the sum of the proper divisors of the other.
Angles: The inclination of one line to another.
Angular Frequency: The frequency of a steady recurring phenomenum in radians per second.
Annulus: The region enclosed by two concentric circles.
Antilogarithm: x=b^y is called the antilogarithm of y to the base b.
Apodize: To apodize is to remove or smooth a sharp discontinuity in a mathematical function, an electrical signal or a mechanical structure.
Arc: Part of a circle.
Arc Length: The distance between the endpoints of an arc along the path of the circle.
Arccos: The inverse of cosine. Note that arccos(A)=cos^-1(x).
Arccot: The inverse of cotangent. Note that arccot(A)=cot^-1(x).
Arccsc: The inverse of cosecant. Note that arccsc(A)=csc^-1(x).
Archimedes Constant: More commonly known as Pi.
Arcminute: Defined as 1/60 of a degree.
Arcsec: The inverse of secant. Note that arcsec(A)=sec^-1(x).
Arcsecond: Defined as 1/360 of a degree.
arcsin: The inverse of sine. Note that arcsin(A)=sin^-1(x).
Arctan: The inverse of tangent. Note that arctan(A)=tan^-1(x).
Arithmetic Coding: Arithmetic coding removes this restriction by representing messages as intervals of the real numbers between 0 and 1.
Arithmetic Mean: The arithmetic mean of n numbers is the sum of the numbers divided by n.
Arithmetic Operators: Symbols and signs used in mathematics.
Asn: The inverse of sine. Note that asn(A)=sin^-1(x).
Autospectrum: A spectrum with the coefficients of the components expressed as the square of the magnitudes
Average: A statistic calculated by summing a set of data values and dividing by the number of values.
Average Deviation: The absolute value of the difference from the mean for each data value, summed, then divided by the number of values.
Averaging: In any process it is often necessary to average a number of measurements to gain any confidence in the measured value.
Axiom: A statement assumed to be true without the need for proof.
Axis: The line, real or imaginary, passing through the centre of an object about which it could rotate; a point of reference.
Axis of Symmetry: A line that passes through a graph or figure such that one side of the figure is an exact mirror image of the other.
Ball: A sphere together with its interior.
Bar Chart: A strong graphical representation of data.
Base: Substance which gives off hydroxide ions (OH^-) in solution. In the expression x^y, x is called the base and y is the exponent.
Basis Function: A mathematical function that can be used to build a description of wavefunctions for electrons in atoms or molecules.
Basis Set: A set of mathematical functions that are combined to approximate the wavefunctions for electrons in atoms and molecules.
Bayes Rule: A rule for finding conditional probability.
Behavioural Envelope: Envelope of response versus frequency.
Beta: A letter of the Greek alphabet.
Bimodal: In the home entertainment context, pertaining to presentations involving the visual and auditory sensory modalities.
Binary: Pertaining to a characteristic that involves the selection, choice, or condition in which there are only two possibilities.
Binary Coded Decimal: A number system where each decimal digit is separately represented by a 4-bit binary code.
Binary Coded Digit: A digit of any number system that is represented as a fixed number of binary digits
Binary Notation: In order to understand how a number in binary notation is constructed, the decimal notation is first discussed.
Binary Number: A number written to base 2.
Binary Point: The radix point that separates powers of two and fractional powers of two in a binary number.
Binomial Theorem: This gives the form of the expansion of any positive integral power of a binomial (x+a)ⁿ as a polynomial.
Biquadratic Equation: A polynomial equation of the 4th degree.
Bisect: Bisect means to cut something in half. For example, to bisect an angle, you would draw a line through the vertex of the angle such that the two angles created are equivalent in measure.
Black Box: A unit whose output is a specified function of the input, but for which the method of converting input to output is not necessarily specified.
Blackman-Harris Window: A weighting that is applied in the time domain to reduce leakage within a Fourier Transform analysis. The Blackman-Harris window has much the same performance as the Kaiser-Bessel window, except that it suppreses the sidelobes more than 92dB at a cost of an 11% wider noise bandwidth.
Blind Experiment: The subjects do not know whether they are in the treatment group or the control group.
Boolean: Pertaining to the operations of formal logic.
Bore: The interior diameter of a cylinder.
Boundary Element Method: A mathematical formulation used to predict acoustic parameters such as pressure and power. This technique may be applied to interior and exterior acoustic problems.
Box: A surface made up of rectangles; a rectangular parallelpided.
Briggsian Logarithm: Another name for the Common Logarithm.
Brun′s Constant: The sum of the reciprocals of all twin primes.
Caliban Puzzle: A logic puzzle in which one is asked to infer one or more facts from a set of given facts.
Canonical Form: In a mathematical context this term is taken to mean a generic or basic representation.
Cartesian Coordinates: Coordinates where the position of a point is described by the distance it is from 2 lines in 2 dimensional space or from 3 planes in 3 dimensional space.
Cartesian Plane: A coordinate plane.
Catalans Constant: = 0.915965594177219015
Cauchy-Schwarz Inequality: The dot product of two vectors cannot be greater in magnitude than the product of the magnitudes of the vectors.
Ceiling Function: The ceiling function of x is the smallest integer greater than or equal to x.
Centillion: A number equal to 10³⁰³.
Central Angle: Angle whose vertex is placed at the center of a circle.
Central Limit Theorem: A random sample of observations from any distribution with a finite mean and a finite variance, the average will tend to follow a normal distribution for large samples.
Centre: A point or axis around which anything revolves or rotates.
Centroid: The centre of mass of a figure.
Cepstrum: A cepstrum is a time history defined as the power spectrum of the logarithm of the Power spectrum.
Cevian: A line segment extending from a vertex of a triangle to the opposite side.
Chord: A line segment that connects two points of a curve or circle.
Circle: The set of points equidistant from a given point.
Circular Cone: A cone whose base is a circle.
Circumference: The perimeter of a circle.
Closed Interval: An interval that includes it′s endpoints.
Coefficient: A coefficient is a constant multiplicative factor of a certain object.
Colinear: In the same line.
Collinear: Points are said to be collinear if they all lie on the same line.
Combinations: A combination is the set itself without reference to order.
Common Fraction: A fraction whose numerator is an integer of smaller value than its denominator.
Common Logarithm: Logarithm in which the base is 10.
Commutative: Describes an operator that gives the same result irrespective of the order of arguments.
Complement: The complement of a subset of a given set is the collection of all elements of the set that are not elements of the subset.
Complementary Angles: Two angles whose sum is 90°.
Complementary Rules: Rules in Boolean Algebra derived from the combination of a single variable with the inverse of itself.
Complex Conjugate: A complex number whose imaginary part is the negative of that of a given complex number, their real parts being equal.
Complex Numbers: A complex number consists of a real and imaginary part.
Complex Numbers, Exponential Form: Exponential expression of complex numbers.
Complex Numbers, Logarithms of: A complex number expressed in logarithmic form.
Complex Numbers, Polar Form: Complex numbers written in polar form.
Composite Number: A natural number that is not prime.
Concave: Curved from the inside.
Concurrent: Pertaining to the occurrence of two or more events or activities within the same specified interval of time.
Congruent: Equilateral, equal, exactly the same size and shape.
Congruent Figures: Two geometric figures that are identical in size and shape.
Conic Section: The cross section of a right circular cone cut by a plane.
Conjecture: A statement that may seem to be true, but has yet to be proven.
Consecutive Sides: Sides of a polygon that share an endpoint.
Consecutive Vertices: Endpoints of a single side of a polygon.
Consistent Linear System: A system of linear equations is consistent if it has at least one solution.
Constant: A quantity that does not change. This quantity may be a number or a variable.
Contour: The outline of an object.
Contraction: A reduction in size.
Control Chart: A chart used to determine whether the distribution of data values generated by a process is stable over time.
Control Group: The subjects in a controlled experiment who do not receive the treatment.
Convex: The curved surface of a cylinder, as a sphere when viewed from without.
Coordinates: Numbers that specify the position of a point or the position or orientation of a geometric object.
Coplanar: A set of points or lines that are all on a common plane.
Coprime: Integers m and n are coprime if the greatest common divisor of m and n is 1.
Corollary to a Theorem: A corollary is a proposition that follows with little or no proof from one other theorem or definition.
Cos: Trigonometric function.
Cosecant: Trigonometric function.
Cosine: Trigonometric function.
Cot: Trigonometric function.
Cotangent: Trigonometric function.
Coterminal Angles: Two angles that have the same terminal side.
Covariance: A measure of the joint variability of a pair of numeric variables.
Cross Correlation: The cross-correlation function gives a measure of the extent to which two signals correlate with each other as a function of the time displacement between them.
Cross Spectrum: The cross spectrum F_xy(f) of f_x(t) and f_y(t) is the forward Fourier Transform of the cross correlation function R_xy(T). The cross spectrum is in general complex.
Cryptarithm: A number puzzle.
Cryptography: Field of mathematics and computer science concerned with information security and related issues, particularly encryption and authentication.
csc: Abbreviation of the trigonometric function cosecant.
Cube: A solid figure bounded by 6 congruent squares.
Cubic Equation: An equation of the third order.
Cumulative Frequency: The number of observations falling in a given class in a frequency table, plus all observations falling in earlier classes.
Cumulative Probability: The probability that a random variable will be less than or equal to a specified value.
Cumulative Relative Frequency: The number of observations falling in a given class in a frequency table, plus all observations falling in earlier classes, divided by the total number of observations.
Curvature: Departure from flatness of a surface. Defined as the reciprocal of the radius of curvature.
Curve Sketching: When sketching a curve there are a number of general features to look for.
Cyclic Polygon: A polygon whose vertices lie on a circle.
Cylinder: A right angle circular cylinder.
Decagon: A polygon with ten sides.
Decillion: A number equal to 10³³.
Decimal: Pertaining to the number representation system with a radix of ten.
Decimal Number: A number written to the base 10.
Deduction: A conclusion derived by reasoning.
Defective Matrix: A matrix A is defective if A has an eigenvalue whose geometric multiplicity is less than its algebraic multiplicity.
Deficient Number: A positive integer that is larger than the sum of its proper divisors.
Degree: A unit describing a plane angle, 1 degree = 1/90 right angle.
Del Operator: The del or grad operation means to take the derivative with respect to distance, in 3 dimensions.
de Moivre: Named after the analyst and probability theorist Abraham de Moivre.
Denominator: The quantity or value on the bottom of a fraction.
Dense Line: The line that contains the shortest path between two points.
Density Function: A mathematical function used to determine probabilities for a continuous random variable.
Dependent Variable: The dependent or response variable is the variable whose behaviour is to be measured as a result of an experiment.
DFT: The Discrete Fourier Transform, the digital version of the fourier transform.
Diagonal Matrix: A diagonal matrix is an n x n matrix with every off diagonal element equal to zero.
Diameter: The longest chord of a figure. In a circle, a diameter is a chord that passes through the centre of the circle.
Differential Equations: Equations that express the rate of change of an equation.
Digit: In the decimal system, one of the numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
Dihedral Angle: The angle formed by two planes meeting in space.
Diophantine Equation: An equation which is required to be solved by integers.
Dirac Delta Function: The limiting case of a pulse with unit area that is infinitely short and at the same time infinitely high.
Direction: The way a number goes - positive or negative.
Disc: A circle together with its interior.
Discontinuity: A break in sequence or continuity of anything.
Discrete: A type of random variable which may take on only a limited set of values, such as 1,2,3,...,10.
Discrete Fourier Transform: The digital version of the fourier transform.
Distribution: A probability function which describes the relative frequency of occurrence of data values when sampled from a population.
Distributive Law: States that if a group of terms connected by like operators contains the same variable, the variable may be removed from the terms and associated with them by the appropriate sign of operation.
Divergence: The divergence operation is performed on a vector and produces a scalar.
Dividend: A number or quantity that is to be divided by another number or quantity.
Division: The binary operation of finding the quotient of two quantities.
Divisor: A number or quantity that is to be divided into another number or quantity.
Dodecagon: A polygon with 12 sides.
Dodecahedron: A solid figure with 12 faces.
Dot: A description of a point in which the point has a definite size.
Dot Product: The dot product of two vectors is obtained by adding the products of the respective components of the vectors.
Duodecimal Number System: The system of numeration with base 12.
e: Natural base of logarithms e=2.718281...
Egyptian Fraction: A number of the form 1/x where x is an integer is called an Egyptian fraction.
Eigenvalue: Possible values for a parameter of an equation for which the solutions will be compatible with the boundary conditions.
Eigenvector of a Matrix: An eigenvector of a square matrix A is a nonzero vector x such that Ax = cx holds for some scalar c.
Elementary Matrix: A matrix that is obtained by performing an elementary row operation on an identity matrix.
Ellipse: A plane through a right angle cone.
Empty Set: The set with no elements in it.
Enneagon: A nine-sided polygon.
Enumerable Set: A countable set.
Equality: The relationship between two quantities that have the same value or values.
Equidistant: The same distance from something.
Equilateral: Equal in length.
Equilateral Triangle: A triangle with three equal sides.
Equivalent Linear Systems: Two systems of linear equations in n unknowns are equivalent if they have the same set of solutions.
Eratosthenes: Around 230BC developed a method for finding all prime numbers.
Errors: No measurement is exact, they all contain some degree of errors.
Estimate: An indication of the value of an unknown quantity based on observed data.
Estimation: The process by which sample data are used to indicate the value of an unknown quantity in a population.
Estimator: Any quantity calculated from the sample data which is used to give information about an unknown quantity in the population.
Euclid: Greek mathematician.
Euclidean Algorithm: A set of rules which when applied to two integers produces their common divisor.
Eulers Constant: γ = 0.5772156…..
Even Function: A function f(x) is called an even function if f(x)=f(-x) for all x.
Even Node: A node that has an even number of arcs.
Even Number: An integer that is divisible by 2.
Exclusive Or: One or the other, but not both.
Expansion: An increase in size.
Exponent: In the expression a^m, m is the exponent and a is the base. a^m is the mth power of a. If this is set equal to y (y=a^m) then this is called an exponential function.
Exponential Constant: The base of natural (Napierian) logarithms e = 2.718281...
Exponential Form of Complex Numbers: Exponential expression of complex numbers.
Exponential Smoothing: A statistical technique commonly used to forecast time series data or to smooth the values on a control chart.
Expression: A validated series of variables, constants, and functions that can be connected by operating symbols to describe a desired computation.
Factor: Numbers or other things that get multiplied.
Factorial: Definition of factorial.
Fast Fourier Transform: An algorithm, or digital calculation routine, that efficiently calculates the discrete Fourier transform from the sampled time waveform.
Fermat Number: The integers F_n=2^2ⁿ+1 are Fermat numbers.
Fermat′s Last Theorem: States that xⁿ+yⁿ=zⁿ has no whole number solutions for n greater than 2.
FFT: An abbreviation of Fast Fourier Transform, an algorithm, or digital calculation routine, that efficiently calculates the discrete Fourier transform from the sampled time waveform.
Fibonacci: His book "Liber Abaci" he introduced Arabic notation for numerals and their algorithms for arithmetic.
Fibonacci Number: A member of the sequence 0, 1, 1, 2, 3, 5,... where each number is the sum of the previous two numbers.
Figure: A geometric form consisting of any combination of points, lines, or planes.
Four Colour Theorem: It is desired to colour a political map on a plane so that countries sharing a common boundary are coloured differently.
Fourier Analysis: A mathematical analysis of waves, discovered by the French mathematician Fourier (1768-1830).
Fourier Transform: The mathematically rigorous operation which transforms from the time domain to the frequency domain and vice versa.
Fractals: Discovered by Benoit Mandelbrot in 1964.
Fraction: A ratio of two integers, or any number that can be expressed as such a ratio.
Galileo Galilei: Astronomer, mathematician and physicist he dwelt, not on the useless question, why do things happen? but, how do things happen?
Game Theory: A branch of mathematics that seeks to model decision making in conflict situations.
GCF: The Greatest Common Factor of two numbers is the largest number that divides into both numbers evenly, with no remainder. For example, the greatest common factor of 60 and 84 is 12.
Genetic Algorithm: A type of optimization algorithm that uses Darwinian principles to evolve a solution to a mathematical model based on survival of the fittest.
Geodesic: The arc on a surface of shortest length joining two given points.
Geodesy: The study of the shape of the Earth, e.g. its deviations from an exact sphere.
Geometric Mean: A statistic calculated by multiplying n data values together and taking the n-th root of the result.
Geometry: The branch of mathematics that deals with the nature of space and the size, shape, and other properties of figures as well as the transformations that preserve these properties.
Given: Information assumed to be true in a proof.
Golden Mean: The proportion of the division of a line so that the smaller part is to the larger part what the larger part is to the whole. This may be applied to the lengths of the sides of a rectangle.
Googol: A number equal to 10¹⁰⁰.
Googolplex: A number equal to 10^googol. Where a googol is 10¹⁰⁰.
Grad Operator: The del or grad operation means to take the derivative with respect to distance, in 3 dimensions.
Grade of a Slope: The pitch of a slope, and is often expressed as a percent tangent, or rise over run.
Graph: A pictorial presentation of the relation between two or more variables.
Graph Paper: Paper that is printed with fine lines making up a regular grid.
Graph Theory: The mathematics of complicated networks.
Great Circle: A circle on the surface of a sphere whose centre is the centre of the sphere.
Greater Than: An inequality that says the variable on the left is greater than the variable to the right of the inequality.
Greater than or Equal to: An inequality that says the variable on the left is greater than or equal to the variable to the right of the inequality.
Greatest Common Divisor: The greatest common factor of two numbers is the largest number that divides into both numbers evenly, with no remainder.
Greatest Common Factor: The greatest common factor of two numbers is the largest number that divides into both numbers evenly, with no remainder. For example, the greatest common factor of 60 and 84 is 12.
Grid: A tesselation of congruent squares sometimes used to measure distance.
Half: One of two equal parts.
Hankel Matrix: A matrix in which all the elements are the same along any diagonal that slopes from northeast to southwest.
Harmonic Mean: The harmonic mean of two numbers a and b is 2ab/(a + b).
Heaviside Function: Also known as the unit step function.
Heaviside Oliver: An English electrical engineer who introduced Laplace transforms into electrical engineering.
Helix: A path formed as a point advances uniformly around a cylinder, as the thread on a screw or the flutes on a drill.
Hemisphere: Half of a sphere.
Heptadecagon: A 17 sided polygon.
Heptagon: A polygon with 7 sides.
Heronian Triangle: A triangle with integer sides and integer area.
Hexadecagon: A 16 sided polygon.
Hexadecimal: Counting system based on 16.
Hexagon: A polygon with 6 sides.
Hexahedron: A polyhedron having 6 faces.
Hidden Line: Broken line used to signify a line that normally would not be seen in a drawing.
Histogram: A graphical display showing the distribution of data values in a sample by dividing the range of the data into non-overlapping intervals and counting the number of values which fall into each interval.
Homogeneous Equations: A differential equation may be described as homogeneous.
Homogeneous Linear System: A system of linear equations Ax = b is homogeneous if b = 0.
Horizontal Line: A line whose slope is zero.
Horizontal Plane: A plane parallel to the surface of the earth.
Horn: A funnel-shaped section.
Huffman Coding: For a given character distribution, by assigning short codes to frequently occurring characters and longer codes to infrequently occurring characters, Huffman's minimum redundancy encoding minimizes the average number of bytes required to represent the characters in a text.
Hyperbola: An open curve with two branches, all points of which have a constant difference in distance from two fixed points called focuses.
Hyperbolic Sine: Hyperbolic sine of x.
Hypotenuse: The longest side of a right triangle.
Hypothesis: A hypothesis is a proposed answer to a problem, or an explanation that accounts for a set of facts and that can be tested by further experimentation and observation. The results of experimentation provide evidence that may or may not support the hypothesis.
Hypothesis Tests: Tests based on a sample of data to determine which of two different states of nature is true.
i: i denotes the imaginary number formed by square rooting negative one.
Icosahedron: A 20 sided solid.
Idempotent Law: Combining a quantity with itself either by logical addition or logical multiplication will result in a logical sum or product that is the equivalent of the quantity.
Identity Law: States that any expression is equal to itself.
IFF: If and only if.
Imaginary Axis: The y-axis of an Argand diagram.
Imaginary Number: i denotes the imaginary number formed by square rooting negative one.
Imaginary Part: The imaginary part of a complex number.
Improper Fractions: A fraction whose numerator is of greater absolute value than it's denominator.
Included Angle: The angle made by two sides of a polygon.
Included Side: The side between two angles in a polygon.
Inclusive Or: One or the other, or both.
Inconsistent Linear System: A system of linear equations is inconsistent if it has no solutions.
Inequality: A relationship between two expressions that are not equal.
Infinite: Becoming large beyond bound.
Infinitesimal: A variable that approaches zero as a limit.
Inflection: A point of inflection of a plane curve is a point where the curve has a stationary tangent, at which the tangent is changing from rotating in one direction to rotating in the oppostie direction.
Initial Side: The side that the measurement of an angle starts from.
Inner Product: The inner or dot product of two vectors is obtained by adding the products of the respective components of the vectors.
Inscribed Angle: The angle formed by two chords of a curve that meet at the same point on the curve.
Integer: A whole number.
Integration: The inverse of differentiation. Mathematical process used in calculus.
Intercept: The point where two lines drawn on a graph cross each other.
Interior of a Circle: The set of points whose distance from the center of the circle is less than that of the radius.
Intersecting Planes: Planes that share a line.
Intersection Law: States that if one input to an AND gate is already TRUE, then the output will depend upon the state of the other inputs only.
Inverse of a Matrix: The matrix B is an inverse for the matrix A if AB = BA = I.
Inverse Proportionality: A relationship in which a quantity is related to the reciprocal of a second quantity.
Inverse Square: A relationship in which a quantity is related to the reciprocal of the square of a second quantity.
Inversely: Inverted or reversed in position or relationship.
Invert: To change a physical or logical state to its opposite state.
Invertible Matrix: A matrix is invertible if it has an inverse.
Irrational Number: Any number that cannot be expressed as the ratio of two integers.
Isometry: A transformation that keeps the same size and shape of a figure but moves it to a new location.
Isosceles Tetrahedron: A tetrahedron in which each pair of opposite sides have the same length.
Isosceles Triangle: A triangle with two equal sides.
j: j is used in engineering and physics to represent i the imaginary number.
Jordan Matrix: A matrix whose diagonal elements are all equal (and nonzero) and whose elements above the principal diagonal are equal to 1, but all other elements are 0.
Jump Discontinuity: A discontinuity in a function where the left and right-hand limits exist but are not equal to each other.
Kalman Filter: A technique for estimating an unknown state of a linear dynamic system given observations of the system which have additive (Gaussian) noise.
Kite: A quadrilateral which has two pairs of adjacent sides equal.
Knight′s Tour: A knight's tour of a chessboard is a sequence of moves by a knight such that each square of the board is visited exactly once.
Lagrangian Points: In a system of two large bodies (Sun-Earth or Earth-Moon), these are the points where a small third body will keep a fixed position relative to the other two.
Laplace Transform: The Laplace transform is used to convert certain types of inital value problems into algebra problems.
Laplacian: The divergence of a gradient.
Latin Square: An n by n array of numbers in which only n numbers appear. No number appears more than once in any row or column.
Latitude: The angular distance of a point on the Earth from the equator.
Lattice Point: A point with integer coordinates.
Least Common Multiple: The least common multiple of a set of integers is the smallest integer that is an exact multiple of every number in the set.
Least Significant Bit (LSB): The bit within a digital word that represents the smallest possible coded value.
Least Squares: Any statistical procedure that involves minimizing the sum of squared differences.
Lemma: A proposition that is useful mainly for the proof of some other theorem.
Lempel-Ziv Welch Compression: Algorithm used by the Unix compress command to reduce the size of files, eg. for archival or transmission.
Leonardo of Pisa: Fibonacci was also known as Leonardo of Pisa.
Leptokurtic: A distribution that is more peaked than a normal distribution.
Less Than: An inequality that says the variable on the left is less than the variable to the right of the inequality.
Less than or Equal to: An inequality that says the variable on the left is less than or equal to the variable to the right of the inequality.
Limit: The number you approach as you plug values into a function, and the values get closer and closer to a given number.
Line: Line is one of the basic undefined terms in Euclidian geometry, but one intuitive definition is as follows: A straight set of points that continue on to infinity in both directions. Although a line is of infinite length, it has thickness and width of zero.
Line of Reflection: The line that is reflected over in a reflection.
Line Segment: A piece of a line which includes two definite endpoints and all points in between them.
Linear: Having an output that varies in direct proportion to the input.
Linear Equations: A first order differential equation is linear if it has the form: y′=A(x)B(y)
ln: Abbreviation of Natural Logarithm.
Locus: The set of all points meeting some specified condition.
log: Abbreviation of Logarithm.
Logarithm: The power to which a base must be raised to yield a given number.
Logarithm of Complex Numbers: A complex number expressed in logarithmic form.
Logic: The study of the formal laws of reasoning.
Logistic Equation: A classical starting point for the dynamics of quasiperiodic and chaotic systems.
Lorentz Transformation: A set of equations which are used, in relativity problems, to transform measurements from one frame of reference to another.
Lowest Common Denominator: The smallest number that is exactly divisible by each denominator of a set of fractions.
LSB: Abbreviation of Least Significant Bit, the bit within a digital word that represents the smallest possible coded value.
Lune: The portion of a sphere between two great semicircles having common endpoints, including the semicircles.
Magic Square: A square array of n numbers such that sum of the n numbers in any row, column, or main diagonal is a constant.
Magic Tour: If a chess piece visits each square of a chessboard in succession, this is called a tour of the chessboard.
Magnitude: The size of a vector quantity.
Major Axis: The major axis of an ellipse is it′s longest chord.
Mandelbrot Set: The most famous fractal, named after Benoit Mandelbrot. It is created by iterating an equation many times.
Mathematical Model: A mathematical representation of a process or physical object.
Mathematical Symbols: Common symbols used in mathematics.
Matrix: A rectangular array of elements.
Maxima: The maxima are points where the value of a function is greater than other surrounding points.
Maximum: In a sample of data, the largest observation.
Mean: The sum of all values in the data, divided by the number of values.
Medial Triangle: The triangle whose vertices are the midpoints of the sides of a given triangle.
Median: A statistic which measures the centre of a set of data by finding that value which divides the data in half.
Mersenne Number: A number of the form 2^p-1 where p is a prime.
Mersenne Prime: A Mersenne number that is prime.
Mesokurtic: A distribution that is normal.
Minima: The minima are points where the value of a function is less than other surrounding points.
Minimum: In a sample of data, the smallest observation.
Minor Axis: The minor axis of an ellipse is its smallest chord.
Minuend: A number from which another number is to be subtracted.
Minus: The symbol: -
Mode: The most frequently occurring value in a sequence of numbers.
Modular Number System: A number system represented best by numbers on a circle because the numbers repeat.
Modulus: The absolute value of a quantity, not considering it's sign or direction.
Monic Polynomial: A polynomial in which the coefficient of the term of highest degree is 1.
Monomial: An algebraic expression consisting of just one term.
Monotone: A sequence is monotone if its terms are increasing or decreasing.
Monotonic: Designating sequences, the successive members of which either consistently increase or decrease but do not oscillate in relative value.
Moving Average: The average of the most recent n data values.
Multiple: The integer b is a multiple of the integer a if there is an integer d such that b=da.
Multiplication: In arithmetic, multiplication of one number, a, by another, b, consists of adding a to itself b times.
Multiplication Factor: The number of times something is multiplied.
Napierian Logarithm: Another name for the Natural or Common Logarithm.
Natural Base of Logarithms: e = 2.71828…
Natural Logarithm: Logarithm in which the base is e.
Natural Number: Any one of the numbers 1, 2, 3, 4, 5, ..
Negation: The process of inverting the value of a function or variable.
Negative: A quantity or value that is less than zero.
Negative Numbers: Numbers that are less than zero are negative numbers.
Network: A group of nodes and arcs.
Newton, Isaac: Newton was a mathematician and natural philosopher (physicist).
Nonagon: A nine sided polygon.
Nonary: Associated with 9.
Nonillion: A number equal to 10³⁰.
Nonsingular Matrix: A square matrix A is nonsingular if the only solution to the equation Ax = 0 is x = 0.
Nonstationary: A characteristic of a time series for which the distribution changes over time.
Normal: A line perpendicular to a surface or curve.
not equal to: A definite statement that the quantity on the left hand side is not equal to the quantity on the right hand side.
Null Set: The null set is a set that contains no objects. Also known as the empty set.
Number: A mathematical entity that may indicate quantity or amount of units.
Number Line: A line on which each point represents a real number.
Number Representation: The representation of numbers by agreed sets of symbols according to agreed rules.
Number System: Any system for the representation of numbers.
Numeral: A numeral is just an object or symbol that stands for a number. For example, 5 is the Arabic numeral for five, and V the Roman numeral for five.
Numerator: The quantity or value on the top of a fraction.
Oblate Spheroid: An ellipsoid produced by rotating an ellipse through 360° about its minor axis.
Oblique Angle: An angle that is not a right angle.
Oblique Coordinates: A coordinate system in which the axes are not perpendicular.
Oblique Triangle: A triangle that is not a right triangle.
Observation: Observations refer to repeated values of a data variable. The rows of a column represent the observations.
Obtuse Angle: An angle larger than 90° but smaller than 180°.
Obtuse Triangle: A triangle that contains an obtuse angle.
Octadecagon: An 18 sided polygon.
Octagon: A polygon with 8 sides.
Octahedron: A polyhedron with 8 faces.
Octal: A number system using the base-8, i.e., each digit can be any of 8 values, represented by the digits 0-7.
Octant: Any one of the 8 portions of space determined by the 3 coordinate planes.
Octillion: A number equal to 10²⁷.
Odd Function: A function f(x) is called an odd function if f(x)=-f(-x) for all x.
Odd Number: An integer that is not divisible by 2.
of the order of: Used when estimating a quantity and means that it is roughly equal to.
Offset Binary Coding: For bipolar signals, offset binary is a digital coding scheme in which the most negative value is represented by all zeros (00000000) and the most positive value is represented by all ones (11111111).
One Dimensional: Having length, but no width e.g. a line.
Open Interval: An interval that does not include its two endpoints.
Opposite Faces: Faces that lie in parallel planes.
Ordinate: The y-coordinate of a point in the plane.
Origin: In Cartesian coordinates, it is the point (0, 0) and located at the intersection of the x- and y-axes.
Orthogonal: Mutually perpendicular.
Orthogonal Matrix: A matrix A is orthogonal if A is invertible and its inverse equals its transpose; i.e., A^-1 = A^T.
Outlier: A data value which is unusual with respect to the group of data in which it is found.
Palindrome: A positive integer whose digits read the same forward and backwards.
Parallel: Two or more lines are said to be parallel if they are in the same plane, but never intersect. Two or more planes are parallel if the planes never intersect.
Parallel Planes: Planes that have no points in common.
Parallelogram: A quadrilateral in which opposite sides are parallel.
Pareto Distribution: A distribution used for random variables which are constrained to be greater or equal to 0.
Pascal′s Triangle: Each number is the sum of the two numbers above. The sum of each row is equal to a power of 2.
Peak: Extreme value of a varying quantity, measured from the zero or mean value.
Pearson Product Moment Correlation Coefficient: A dimensionless index that reflects the extent of a linear relationship between two data sets.
Pentadecagon: A 15 sided polygon.
Pentagon: A polygon with five sides.
Perfect Cube: An integer is a perfect cube if it is of the form m³ where m is an integer.
Perfect Number: A positive integer that is equal to the sum of its proper divisors.
Perfect Power: An integer is a perfect power if it is of the form mⁿ where m and n are integers and n>1.
Perfect Square: An integer is a perfect square if it is of the form m² where m is an integer.
Perimeter: The distance around the outside of a shape.
Permutations and Combinations: A permutation is a particular sequence of a given set of objects. A combination is the set itself without reference to order.
Perpendicular: At right angles to. A line at right angles to another line or to a plane.
Perspective: A feeling of depth.
Perspective Drawing: A drawing in which, in order to show perspective, oblique parallel lines will meet.
pi: A letter of the Greek alphabet. The lowercase is used to denote the number of times the diameter of a circle can be divided into the circumference.
Pie Chart: A strong representation of data with the size of the slice representing the fraction of the total.
Plane: A two-dimensional group of points that goes on infinitely in all directions; made up of infinite lines.
Plane Angle: The plane angle between two radii of a circle which cut off on the circumference an arc equal in length to the radius is 1 radian.
Plane Section: The intersection of a figure with a plane.
Plato: A Greek philosopher, pupil of Socrates and Aristotle′s teacher.
Platykurtic: A distribution that is less peaked than a normal distribution.
Plus: The symbol: +
Point: A zero-dimensional figure.
Poisson Equation: A fundamental equation of mathematical physics, describing the spatial variation of a potential function for given source terms.
Polar Coordinates: The position of a point is defined as the distance from the origin and an angle relative to the x axis.
Polar Form of Complex Numbers: Complex numbers written in polar form.
Polygon: A shape of multiple sides. Regular polygons have sides of equal length.
Polyhedral: In the shape of a solid formed by plane faces, as in a prism.
Polynomial: A function that is a sum of power functions, with positive integer exponents, multiplied by constants.
Population: The total number of unique values.
Positional Notation: A numbering system in which a number is represented by means of a stated set of symbols or digits, such that the value contributed by each symbol or digit depends upon its position as well as upon its value.
Positional Weighting: The value given a digit based on the digit′s position within a given number.
Positive: A quantity or value that is greater than zero.
Positive Logic: The form of logic in which the more positive logic level represents 1 and the more negative level represents 0.
Postulate: A statement assumed to be true without proof.
Power Factor: The cosine of the phase angle between voltage and current.
Practical Number: A positive integer m such that every natural number n not exceeding m is a sum of distinct divisors of m.
Prime Numbers: A prime number has only two different factors. They are 1 and the number itself. 13 is a prime number because the only factors of 13 are 1 and 13. Note that 1 is not a prime number.
Primitive Pythagorean Triangle: A right triangle whose sides are relatively prime integers.
Principal Component Analysis: Constructing new features which are the principal components of a data set.
Principal Curve: A nonlinear principal component axis.
Probability: A number between 0 and 1 which represents how likely an event is to occur.
Prolate Spheroid: An ellipsoid of revolution, the longer axis of which is the axis of revolution.
Pronic Number: A number of the form n(n+1).
Proper Fractions: A fraction whose numerator is of lower absolute value than it's denominator.
Proportion: A statement of equality between two ratios.
Proportionality: A relationship in which a quantity is related to the second quantity.
Protractor: A tool used to measure angles.
PSD: A method of scaling the amplitude axis of spectra of random rather than deterministic signals.
psi: A letter of the Greek alphabet.
Pythagoras: Greek philosopher and mathematician; held that numbers were basic to matter.
Pythagoras Theorem: The Square on the Hypotenuse is equal to the sum of the squares of the other two sides.
Pythagorean Triangle: A right triangle whose sides are integers.
Pythagorean Triple: An ordered set of three positive integers (a,b,c) such that a²+b²=c².
QED: Abbreviation for quod erat demonstrandum, used to denote the end of a proof.
Quadrangle: A four-sided polygon.
Quadratic Equation: An equation of the second order.
Quadridecagon: A 14 sided polygon.
Quadrilateral: A four sided polygon.
Quadrillion: A number equal to 10¹⁵.
Quart: A unit of volume.
Quarter: One of four equal parts. An outdated British unit of weight 1 quarter = 28 pounds (lb).
Quartic: A polynomial equation of degree 4.
Quartiles: Statistics which divide the observations in a numeric sample into 4 intervals, each containing 25% of the data.
Quintic: A polynomial equation of degree 5.
Quintile: Statistics which divide the observations in a numeric sample into 5 intervals.
Quintillion: A number equal to 10¹⁸.
Quod Erat Demonstrandum: Normally abbreviated as QED and used to denote the end of a proof.
Quotient: The result when one number or quantity is divided by another.
rad: An abbreviation of radian the SI unit of plane angle.
Radial: A direction perpendicular to the centreline of a shaft.
Radian: The radian is the plane angle between two radii of a circle which cut off on the circumference an arc equal in length to the radius.
Radii: Plural of radius.
Radius: In a circle, the radius is the distance from the centre of the circle to a point on the circle.
Radix: The number of distinct symbols used in a number system.
Random Noise: A noise signal, commonly used in measurements, which has constantly shifting amplitude, phase, and a uniform spectral distribution of energy.
Random Process: A random process is a collection of time-history records that can be described by appropriate statistical parameters, such as averaged properties of these records at a number of fixed times.
Random Sampling: A sampling method in which all elements in the population have an equal chance of being selected.
Ratio: The quotient of two numbers.
Rational B-Spline: equation that permits the modeling of free-form curves between two endpoints as a function of a set of intermediate points whose values influence the shape of the curve.
Rational Number: Any number that can be expressed as the ratio of two integers.
Rayleigh′s Method: A method used for calculating approximate natural frequencies for a vibrating system assuming a deflected shape and balancing kinetic and strain energies.
Real Axis: The x-axis of an Argand diagram.
Real Number: Any of the conventional numbers, including fractions and irrationals.
Recency Effect: An increase in correct recall rate for the most recently presented items of a list compared with those presented earlier in the list.
Reciprocal: A number that is made into a fraction.The reciprocal of 2 is 1/2.
Rectangle: A quadrilateral with 4 right angles.
Rectangular Coordinates: Coordinates where the position of a point is described by the distance it is from 2 lines in 2 dimensional space or from 3 planes in 3 dimensional space.
Reflex Angle: An angle between 180° and 360°.
Relative Frequency: A count of the number of occurrences of a data value in a sample, or the number of values falling within a fixed range, expressed as a proportion of the total number of observations.
Relatively Prime: If the greatest common divisor of a and b is 1 then a and b are known as relatively prime.
Resolver: A rotary, electromechanical device used to perform trigonometric computations by varying the magnetic couplings between its primary and secondary windings.
Revolution: A rotation through a full circle, or 360 degrees.
Rhombus: A parallelogram with four equal sides.
Right Triangle: A triangle that contains a right angle.
Roman Numerals: The roman number system with decimal equivalents.
Root: A root of a polynomial function, f, is just a solution to the equation f(x) = 0, that is an input that yields an output of 0.
Rotation: Motion of an object where the path of every point is a circle or circular arc.
Round-Off Error: The error accumulated during a calculation due to rounding intermediate results.
Row Equivalent Matrices: Two matrices are row equivalent if one can be obtained from the other by a sequence of elementary row operations.
Ruled Surface: A surface formed by moving a straight line.
Sample: A set of observations, usually considered to have been taken from a much larger population.
Scalar Product: The scalar or dot product of two vectors is obtained by adding the products of the respective components of the vectors.
Scientific Notation: Numbers entered as a number from one to ten multiplied by a power of ten.
Separable Equations: A differential equation is separable if it can be written: y′=A(x)B(y)
Septagon: A seven-sided polygon.
Septet: A unit of quantity equal to 7.
Septillion: A number equal to 10²⁴.
Series: The sum of a finite or infinite sequence.
Set: A collection of objects called elements.
Sexadecimal: The same as Hexadecimal.
Sexagesimal: In the sexagesimal system calculations are done in the base 60 as used by the Ancient Babylonians.
Sextet: A unit of quantity equal to 6.
Sextillion: A number equal to 10²¹.
Shapiro-Wilks Test: A test to determine whether or not a sample comes from a normal distribution.
Sign: The sympol that states whether a number is positive (+) or negative (-). If a sign is not placed immediately before a number, it is taken as positive.
Signs and Symbols: A list of signs and symbols.
Simple Fraction: A fraction whose numerator is an integer of smaller value than its denominator.
Sinc Function: The function sin of x divided by x.
Sine: Trigonometrical function.
Singular Matrix: A square matrix A is singular if the equation Ax = 0 has a nonzero solution for x.
Sinusoidal: Having the form of a sine wave.
Skew: An expression of the so-called "third moment".
Skewness: Skewness defines the degree of asymmetry of the distribution around its central value.
Slide Rule: A calculating device consisting of two sliding logarithmic scales.
Slope: The measure of the tilt of a line, the rise over run or how much the line moves up for every movement to the right.
Small Circle: The circle formed by the intersection of a sphere and a plane that doesn't contain the centre of the sphere.
Smoothing: Smoothing techniques are used to reduce irregularities in time series data.
Socrates: Greek philosopher; emphasized the study of human nature in relationship to society.
Solid Geometry: The study of figures in three-dimensional space.
Solid of Revolution: A solid formed by rotation a plane figure about an axis in three-space.
Space: The set of all possible points; made up of infinite planes.
Special Constants: A list of Mathematical constansts and their formulations.
Sphere: Basic calculations of the properties of a sphere.
Spherical Coordinates: A point is located in space by the distance from the origin and two angles.
Spherical Triangles: A triangle on the surface of a unit sphere.
Spherical Trigonometry: The branch of mathematics dealing with measurements on the sphere.
Square: A number raised to the power 2 ie 2 x 2 = 2² = 4. Also, a 2 dimensional figure with the height and width having the same lengths,and at right angles to each other.
Square Root: The square root of a number is a number that when multiplied by itself equals the number that the square root is being taken of.
Square Surface: A surface at a right angle with another surface.
Standard Differential Equations: A listing of some of the standard differential equations.
Standard Error: The standard deviation divided by the square root of the number of data values.
Standard Integrals: A listing of the standard indefinite and definite integrals.
Standard Normal Distribution: A normal distribution with a mean equal to 0 and a standard deviation equal to 1
Standardized Kurtosis: A standardized form of the kurtosis statistic which renders the statistic free of scale.
Standardized Skewness: A standardized form of the skewness statistic which renders the statistic free of scale.
Statistical Model: A statistical model is used to describe the relationship between a dependent variable Y and one or more independent variables.
Straight Angle: An angle whose measure is 180 degrees.
Straight Line: A straight set of points that continue on to infinity in both directions.
Straightedge: As it sounds, an unmarked tool used to draw straight lines.
Student′s t Distribution: A probability distribution which is very similar in shape to the standard normal distribution.
Subset: A subset of a given set is a collection of things that belong to the original set.
Subtrahend: A number that is to be subtracted from another number.
Sum: The result of the addition of numbers.
Supplementary Angles: Two angles are supplementary if they add up to 180°.
Surd: Used in mathematics to describe an irrational quantity.
Surface Area: The total area of the surface of a solid.
Symbolic Logic: A mathematical form in which propositions and their relationships may be represented symbolically.
Symmetric Matrix: A matrix A is symmetric if it equals its transpose.
Tangent: Trigonometric function.
Target Population: The entire group a researcher is interested in, the group about which the researcher wishes to draw conclusions.
Terminal Side: The side that the measurement of an angle ends at.
Tesselation: A covering of a plane with congruent copies of the same region with no holes or overlaps.
Tetragon: A four-sided polygon.
Thousand: A number equal to 10³.
Three Dimensional: Having length, width, and thickness i.e. space.
Tilt: The measure of an angle as compared to a horizontal line.
Timeline: A brief overview of the major milestones in science and engineering.
Toeplitz Matrix: A matrix in which all the elements are the same along any diagonal that slopes from northwest to southeast.
Tomography: Mathematical techniques for reconstructing three dimensional volumes from the integrated projections along rays.
Torus: A geometric solid in the shape of a doughnut.
Trace: The trace of a matrix is the sum of the terms along the principal diagonal.
Transcendental: Not algebraic.
Transform: A transform is a mathematical operation that converts a function from one domain to another domain with no loss of information.
Transversal: A line that intersects 2 others.
Transversible: A network in which all arcs can be traced without going over one more than once.
Trapezoid: A quadrilateral that has at least one pair of parallel sides.
Triad: A unit of quantity equal to three.
Triangle: A three sided shape.
Triangulation: In general, the unique location of the source from some combination of at least three ranges and/or bearings in three dimensional space.
Tridecagon: A 13 sided polygon.
Trigon: A three-sided polygon - a triangle.
Trilateration: Method of surveying wherein the lengths of the triangle sides are measured.
Trillion: A number equal to 10¹².
Triple: A group of three items.
Truncated Paraboloid: A paraboloid reflector that has been cut away at the top and bottom.
Truncation Error: Error resulting from the use of only a finite number of terms of an infinite series or from the approximation of operations.
t test: A hypothesis test based on Student′s t distribution.
Twin Primes: Two prime numbers that differ by 2. eg 11 and 13.
Two Dimensional: Having both width and length, but no thickness.
Undecagon: An eleven sided polygon.
Unit Circle: A circle with radius 1.
Unit Cube: A cube with edge length 1.
Unit Fraction: A fraction whose numerator is 1.
Unit Square: A square of side length 1.
Unity: One.
Universal Statement: A conditional that uses the words "all" or "everything".
Upper Quartile: The 75th percentile, calculated by ordering the data from smallest to largest and finding the value which lies 75% of the way up through the data.
Vanishing Line: The horizon; in a drawing it is at the height of viewer′s eye.
Vanishing Point: The point in space where two parallel lines seem to meet.
Variable: A letter that is used to represent a numerical quantity whose value may or may not yet be known.
Variance: The square of the difference from the mean for each data value, summed and divided by one less than the number of values.
Versus: As a function of, as distance versus time.
Vertical: The direction of gravity at the point of observation.
Vertical Angles: Two angles that share a common vertex and whose sides form 2 lines.
Vertical Axis: On a graph, the straight line axis that is plotted from bottom to top, the y axis.
Vertical Line: A line that goes straight up and down, and whose slope is defined as infinite or undefined.
Vertical Plane: An imaginary plane that is perpendicular to the horizontal plane.
Vigesimal: Related to intervals of 20.
Vinculum: The horizontal bar in a fraction separating the numerator from the denominator.
Vulgar Fraction: A rational number expressed as a ratio rather than as a decimal fraction.
Warning Limits: Limits placed on a control chart for variables or attributes at 1 and 2 sigma to help determine how far points lie from the centerline.
Waterfall Plot: A series of spectral maps taken at regular intervals of time or at regularly spaced shaft speeds, similar to the flow of a waterfall.
Weibull Distribution: A distribution used for random variables which are constrained to be greater or equal to 0.
Winding Number: The number of times a closed curve in the plane passes around a given point in the counter clockwise direction.
Working Stress: The allowable stress considered to be safe in the design of part. It is the ultimate stress of the material divided by a safety factor.
x axis: The horizontal axis in the plane.
X-Intercept: The point at which a line crosses the x-axis.
y axis: The vertical axis in the plane.
Y-Intercept: The point at which a line crosses the y-axis.
Z Axis: Axis perpendicular to both X and Y axes.
Zero Angle: An angle whose measure is 0.
Zero Dimensional: Having no dimension; a point.
Z-Intercept: The point at which a line crosses the z-axis.