Iron is one of the most abundant metallic elements (41000 ppm) and probably one of the most important, being used on the largest scale of any metal.
Chemical formula for Iron III Oxide.
Feather Edge
A fine tapered edge of material or where one blends into another.
Chemical formula for Iron II Chloride.
Chemical formula for Iron III Chloride.
Feed Pipe
A pipe supplying liquid or gas.
Feed Pump
A pump supplying liquid or gas.
Occurs when some or all of the output of the device (such as an amplifier) is taken back to the input.
Feedback Control
Another name for Closed Loop control.
A transmission line that carries energy to the antenna.
A horn radiator used to feed a reflector.
Feeler Gauges
A set of steel fingers of different thicknesses that can be used to set the gap between two objects.
The plural of foot. One foot was defined as one third of the Imperial Standard yard. The abbreviation of foot is ft
Feet per Minute
Old imperial units of velocity, abbreviated as fpm or ft min-1.
Feet per Second Squared
Old imperial unit of acceleration.
Feigendaum Constants
Two mathematical constants.
Finite element method is a numerical method which is used to calculate displacements or stresses in structures or components subjected to external and internal loads.
Female Part
A concave piece of equipment which receives a mating male, convex, part.
Female Thread
An internal screw thread designed to mate with a component having male threads of the same size and type.
Prefix representing a multiplication of 10-15
Abbreviated as fm, unit of distance equal to 10-15m.
Abbreviated as fs, unit of time equal to 10-15s.
The thigh bone in humans.
A straight guide on a tool such as a table saw or router table to keep the material a set parallel distance from the blade or cutter.
Fender Washer
An oversize washer used to spread the load further on soft or thin materials.
Chemical formula for Iron II Oxide.
Fermat Number
The integers Fn=22n+1 are Fermat numbers.
Fermat′s Last Theorem
States that xn+yn=zn has no whole number solutions for n greater than 2.
Fermat′s Principle
The path taken by a ray of light between any two points in a system is always the path that takes the least time.
Fermat′s Spiral
A parabolic spiral.
A class of biochemical reactions that break down complex organic molecules into simpler materials.
A derived SI Unit of length equal to 10-15m
Fermi Constant
The Fermi constant shows the coupling between a nucleon and a lepton field.
Fermi Energy
The average energy per particle when adding particles to a distribution but without changing the entropy or the volume.
Fermi Enrico
He received the Nobel Prize for physics for the development of neutron-induced nuclear reactions in 1938.
Fermi Level
Energy level at which the probability of finding an electron is one-half.
Fermions are particles that satisfy the Pauli exclusion principle and obey the Fermi-Dirac statistics of statistical mechanics.
A man-made element with an atomic number of 100.
Ferranti, Sebastian de
High voltage ac generation and transmission.
Ferric Oxide
Old name for Iron III Oxide.
Material that has populations of atoms with opposing magnetic moments, the opposing moments are unequal and a spontaneous magnetization remains.
A solid solution of one or more elements in body-centered cubic iron.
Ferrite Bead
A passive electric component used to suppress high frequency noise in electronic circuits, employing the mechanism of high dissipation of high frequency currents in a ferrite to give high frequency noise suppression.
Ferrite Rod Aerial
A coil of wire wound on a ferrite material to increase the inductance of the coil. It's signal capturing capability.
A dielectric material that may exhibit polarization in the absence of an electric field.
Spontaneous alignment of electric dipoles within a material under the influence of an electric field, resulting in a hysteresis loop when the direction of electric field is switched.


A blood-red complex of Fe2+ ion with 1,10-phenanthroline, used as a redox indicator. Ferroin changes from red to pale blue when oxidized.

Ferromagnetic Material
A highly magnetic material, such as iron, cobalt, nickel, or their alloys.
Permanent and large magnetizations found in some metals (e.g., Fe, Ni, and Co), which result from the parallel alignments of neighboring magnetic moments.
Ferrous Chloride
Old name for Iron II Chloride.
Ferrous Metal
A metal alloy in which iron is the major ingredient.
Ferrous Oxide
Old name for Iron II Oxide.
Ferrous Sulphide
Old name for Iron Sulphide.
Latin for iron, hence the symbol Fe.
The joining of the male and female gametes.
A substance added to soil to provide nutrients for plants.
Chemical formula for Iron Sulphide.
Chemical formula for Iron II Sulphide.
Chemical formula for Iron II Sulphate.
Festoon Bulb
A light bulb in the form of a small glass tube with caps at each end providing the contacts.
A data transfer in which the data bytes are transferred from the source to the controller, and then from the controller to the target.