So

SO2
Chemical formula for Sulphur Dioxide.
Soap
A salt of a fatty acid.
SoC
Abbreviation of State of Charge.
Sociocusis
Loss of hearing caused by noise exposures that are part of the social environment, exclusive of occupational-noise exposure, physiological changes with age, and disease.
Socket Bolt
Fastened with a hexagonal Allen key.
Socket Wrench
A tool with socket end or a drive tool combined with a socket.
Socrates
Greek philosopher; emphasized the study of human nature in relationship to society.
Soda Ash
Alternative name for Sodium Carbonate.
Sodium
A soft, silvery coloured metal which, like other members of the alkali group of metals, is extremely reactive.
Sodium Carbonate

Na2CO3

Commonly known as washing soda or soda ash. Synthetically produced in large quantities from common salt using the Solvay process.

Sodium Chloride

NaCl

Commonly known as table salt.

Sodium Glutamate
More commonly known as Monosodium Glutamate.
Sodium Hydride

NaH

White to silver coloured solid.

Sodium Hydroxide

NaOH

A caustic metallic base used in the manufacture of pulp, textiles, drinking water, soaps and detergents.

Sodium Hypochlorite

NaOCl

Sold as a solution under a variety of trade names for use as liquid bleach.

Sodium I Bromide

NaBr

White crystalline solid.

Sodium I Fluoride

NaF

White crystalline solid.

Sodium I Iodide

NaI

White crystalline solid.

Sodium I Oxide

NaO2

Yellow crystalline solid.

Sodium Nickel Chloride Battery
This consists of a negative liquid sodium electrode and a solid positive electrode containing nickel chloride and nickel.
Sodium Nitrate

NaNO3

A white solid which is very soluble in water, used as an ingredient in fertilizers, explosives, and in solid rocket propellants, as well as in glass and pottery enamels.

Sodium Oxide

Na2O

White solid.

Sodium Peroxide

Na2O2

Pale yellow solid.

Sodium Silicate

Na2O3Si

Available in aqueous solution and in solid form and is used in cements, passive fire protection, refractories, textile and lumber processing, and automobiles.

Sodium Sulphur Battery
Uses a solid electrolyte of beta aluminium and liquid electrodes of molten sulphur and sodium.
Sodium Superoxide
Old name for Sodium I Oxide.
SOFC
Abbreviation of Solid Oxide Fuel Cell.
Soffit
The undersurface of a horizontal element of a building, especially the undersides of a stair or roof overhang.
Soft Foot
A term used to describe any condition where tightening or loosening the bolts of the machine feet distorts the machine frame.
Soft Room
Room with highly sound absorptive surfaces.
Soft Solder
Solder composed of 50% Tin and 50% Lead
Soft X-Rays
Band of low energy X-rays, between 0.1 keV and approximately 5 keV.
Soft-Ground Tunnel
A passage constructed through loose, unstable, or wet ground, requiring supports to keep the walls from collapsing.
Soil Bulk Electrical Conductivity
Conductivity of electricity through soil.
Soil Heat Flux
The amount of heat flowing into a cross-sectional area of soil per unit time.
Soil Volumetric Water Content
The proportion of a volume of soil that is water.
Sol
A colloid with solid particles suspended in a liquid.
Solar Air Mass
The optical air mass penetrated by light from the sun for any given position of the sun in the sky.
Solar Cell
A cell that produces current under sunlight.
Solar Constant
The bolometric flux at a distance of 1 AU from the sun = 1.368x103Wm-2
Solar Cycle
The approximately 11 year quasi-periodic variation in frequency or number of solar active events.
Solar Data
Equatorial radius, mass, solar constant,…
Solar Day
The day defined as one revolution of the Earth on its axis with respect to the Sun.
Solar Eclipse
When the Earth enters the Moon′s shadow as the Moon moves wholly or partially in front of the Sun as seen from Earth.
Solar Flare
Sudden violent explosion on the Sun which occurs above complex active regions in the photosphere.
Solar Protons
Protons emitted by the sun, especially during solar flares.
Solar Storm
Violent outburst of explosive activity on the Sun.
Solar System
Meaning our sun and all of the bodies that orbit the sun.
Solar Wind
The wind from the Sun. More specifically, particles, usually electrons and protons, continually streaming away from the corona of the Sun.
Solder
A low melting point alloy that can wet copper, conduct current, and mechanically join conductors.
Solder Balls
Small spheres of solder adhering to the laminate, mask, or conductor surfaces usually after wave or reflow soldering.
Solder Bridging
When solder paste or solder on two or more adjacent pads come into contact to form a conductive path or bridge.
Solder Mask
A dielectric material used to cover the entire surface, except where the joints are to be formed, of a PCB primarily to protect the circuitry from environmental damage.
Solder Paste
Mixture of minute spherical solder particles, activators, solvent, and a gelling or suspension agent.
Soldering
Process of joining metallic surfaces with solder without melting the base material.
Soldier
A brick laid on its end, with its narrow face toward the outside of the wall.
Solenoid
An electromagnetic device that changes electrical energy into mechanical motion.
Solid
Matter with a definite size and shape.
Solid Axle
Suspension where left and right wheels are rigidly connected except torsionally.
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.
Solid Oxide Fuel Cell
A fuel cell that employs a solid, ionically conductive material as electrolyte.
Solid Rocket
A rocket that uses a solid propellant.
Solid Solution
A single solid homogeneous crystalline phase containing two or more chemical species.
Solid State Device
An electronic device that operates by the movement of electrons within a solid piece of semiconductor material.
Solidification
The change from liquid state to solid state upon cooling through the melting temperature or melting range.
Solidification Range
The temperature between the liquidus and solidus.
Solidification Shrinkage Crack
A crack that forms due to internal stresses developed from shrinkage during solidification of a metal casting; also called a hot crack.
Solidus
In a constitution or equilibrium diagram, the locus of points representing the temperatures at which various compositions finish freezing on cooling or begin to melt on heating.
Solubility
The solubility of a substance is its concentration in a saturated solution.
Solubility Product
The equilibrium constant for a reaction in which a solid ionic compound dissolves to give its constituent ions in solution.
Solubilizing Group
A group or substructure on a molecule that increases the molecule′s solubility.
Soluble
Capable of being dissolved in a solvent, usually water.
Soluble Salt
An ionic compound that dissolves in a solvent, usually water.
Solute
What is dissolved in a solution.
Solution
Mixture of a solid and a liquid where the solid never settles out.
Solution Heat Treatment
Heating an alloy to a suitable temperature, holding at that temperature long enough to allow one or more constituents to enter into solid solution, and then cooling rapidly enough to hold the constituents in solution.
Solvent
Liquid in which something is dissolved, eg the water in saltwater.
Solvent Extraction
A method for separating mixtures by exploiting differences in the solubilities of the components.
Solvus
The curve on a phase equilibrium diagram that defines the limits of solid solubility.
Somatic Cells
Body cells. All the cells except the germ-line cells.
Sonar
Sound waves in water.
Sone
The unit of measurement for loudness. One sone is the loudness of a sound whose loudness level is 40 phons.
Sonic
Pertaining to sounds capable of being heard by the human ear.
Sonic Boom
A body moving through the air pushes the air aside. If the body moves at or greater than the speed of sound a sonic boom is observed.
Sonic Delay Line
A device used in a communications link or a computer memory in which the signal is delayed by the propagation of a sound wave. Also known as an Acoustic Delay Line.
Sonobuoy
An instrument designed to receive sound energy underwater and transmit a corresponding signal in the atmosphere at radio frequencies.
Sonoluminescence
Light emission from small cavitating bubbles of air or other gas in water or other fluids, produced when the fluid is acted upon by intense high frequency sound waves.
Soot
Sub-micron size particles, primarily carbon, created in combustion as products of incomplete combustion.
Sorb
To take up gas by sorption.
Sorbate
Gas taken up by a sorbent.
Sorbent
The material which takes up gas by sorption.
Sorption
Assimilation of molecules of one substance by a material in a different phase.
Sound
Energy that is transmitted by pressure waves in air or other materials and is the objective cause of the sensation of hearing.
Sound Absorption
Reduction of sound pressure level through sound absorption.
Sound Absorption Coefficient
The practical unit between 0 and 1 expressing the absorbing efficiency of a material. It is determined experimentally.
Sound Attenuation
The reduction of the intensity of sound as it travels from the source to a receiving location.
Sound Barrier
Concept that the speed of sound, or sonic speed, constitutes a speed limit to flight through the atmosphere.
Sound Definition
This compares ‘useful’ sound with total sound.
Sound Energy
Energy added to an elastic medium by the presence of sound, consisting of potential energy in the form of deviations from static pressure and of kinetic energy in the form of particle velocity.
Sound Energy Density
The quotient obtained when the sound energy in a region is divided by the volume of the region.
Sound Energy Flux
The average rate of flow of sound energy for one period through any specified area.
Sound Energy Flux Density
This is Sound Intensity.
Sound Exposure Level
Used to describe the amount of noise from an event such as an individual aircraft flyover.
Sound Field
A region containing sound waves. Normally broken down into Near Field and Far Field.
Sound Focusing
Focusing of sound can be caused by reflection from large concave surfaces.
Sound Growth
The growth of sound in the room.
Sound Insulation
The capacity of a structure to prevent sound from reaching a receiving location.
Sound Intensity
The quotient obtained when the average rate of energy flow in a specified direction and sense is divided by the area, perpendicular to that direction, through or toward which it flows.
Sound Isolation
The degree of acoustical separation between two locations, especially adjacent rooms.
Sound Level
Of airborne sound, a sound pressure level obtained using a signal to which a standard frequency-weighting has been applied.
Sound Level Meter
Device used to measure sound pressure level.
Sound Masking
The process of using electronic masking sound to cover unwanted or intrusive sound such as speech or equipment noise, typically used to enhance speech privacy and productivity.
Sound Power
In a specified frequency band, the rate at which acoustic energy is radiated from a source. In general, the rate of flow of sound energy, whether from a source, through an area, or into an absorber.
Sound Power Level
Of airborne sound, ten times the common logarithm of the ratio of the sound power under consideration of the standard reference power of 1 pW. The quantity so obtained is expressed in decibels.
Sound Pressure
A fluctuating pressure superimposed on the static pressure by the presence of sound.
Sound Pressure Level
Ten times the logarithm of the ratio of the time-mean-square pressure of a sound to the square of the reference sound pressure.
Sound Propagation
At distances large compared to the size of the source, sound intensity diminishes according to the inverse square law.
Sound Quality
Pertaining to the quality or other aspects of the machine that might be inferred from the sound it makes.
Sound Receiver
One or more observation points at which sound is evaluated or measured. The effect of sound on an individual receiver is usually evaluated by measurements near the ear or close by.
Sound Transmission Class
In acoustics, a single number rating for describing sound transmission loss of a wall or partition.
Sound Transmission Coefficient
Of a partition, in a specified frequency band, the fraction of the airborne sound power incident on the partition that is transmitted by the partition and radiated on the other side.
Sound Transmission Loss
Of a partition, in a specified frequency band, ten times the common logarithm of the ratio of the airborne sound power incident on the partition to the sound power transmitted by the partition and radiated on the other side.
Sound Waves
Sound waves can be thought of like the waves in water.
Soundcard
Expansion card which enables the PC to make sounds.
Sounding
Any probe of the environment made to obtain information at various levels.
Soundstage
A listening term that refers to the placement of a stereo image in a fashion that replicates the original performance.
Sour Water
Waste waters containing fetid materials, usually sulphur compounds.
Source
The object that produces the wave or disturbance.
Source Room
In architectural acoustical measurements, the room that contains the noise source or sources.
Source Route
The route that a packet takes to reach its destination. The route is determined prior to the start of the transmission of the packet.
Southern Blot
A DNA hybridization procedure in which specific DNA fragments are detected in a mixture by means of a complementary, labelled nucleic acid probe.