A slice of semiconductor material upon which monolithic ICs are produced.
Wafer Switch
A rotary switch in which the contacts are arranged on levels.
A wall facing, usually of wood, cut stone, or ceramic tile, that is carried only part way up a wall.
Solid structure that defines and sometimes protects an area.
Wall Cloud
An abrupt lowering of a cloud from its parent cloud base, a cumulonimbus or supercell, with no visible precipitation underneath.
Wall Plug
A piece of plastic, wood or fibre that is inserted into a drilled hole in masonry to allow a woodscrew to be fitted.
Wallace, Alfred Russel
One of the 19th century′s most remarkable intellectuals. Not only did he co-discover the process of evolution by natural selection with Charles Darwin in 1858, but he also made very many other significant contributions, not just to biology, but also to subjects as diverse as glaciology, land reform, anthropology, ethnography, epidemiology, and astrobiology.
Wallis, Barnes
British engineer and inventor famous for the R100, Wellington bomber and the bouncing bombs.
Cross grained wood used for ornamental work.
Abbreviation of Wide Area Network.
Wankel Engine
A rotary engine with a rotor rotating in an oval cylinder. Named after it′s designer Felix Wankel.
Wankel, Felix Heinrich
Inventor and developer of the wankel engine, a rotary engine.
Warburg, Otto H
German biochemist who was awarded a Nobel Prize in 1931 for his contributions to cellular metabolism.
Warm Working
Plastically deforming metal above room temperature but below the temperature at which the material undergoes recrystallization.
A term that is used to describe a listening term in terms of frequency, generally considered the range from approximately 150Hz-400Hz.
Warning Lamp
A small lamp that will light up if there is a problem.
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.
The yarns running lengthwise and parallel to the selvage in a woven fabric.
Warren Truss
Structural framework for supporting loads over long spans.
Used to distribute load under a nut or bolt locking surface.
Washing Soda
Alternative name for Sodium Carbonate.
Washout Plug
A small mudhole used for washing out the boiler.
Waste Gate
A valve used to limit the boost developed in a turbocharger.
Waste Water
The used water and solids from industrial processes that flow to a treatment plant.
A traditional unit of time equal to 4 hours.
A colourless, tasteless liquid with some very peculiar properties that stem from the bent H-O-H structure of its molecules.
Water Absorption
A materials tendency or lack of to absorb water.
Water Cooling System
Water passes through the system or through a water cooling jack, this is then sent to a radiator where air is passed over the radiator to remove the heat from the water before it is sent back to the system to be cooled.
Water Cycle
Also known as the Hydrologic Cycle.
Water Electrolysis
Process for the electrochemical decomposition of water in a divided electrolytic cell by electrolysis.
Water Gas
A fuel gas used in industrial synthesis of organic chemicals, and in welding, glassmaking, and other high-temperature industrial applications.

Water Glass
Old name for Sodium Silicate.
Water Glycol Fluid
A fluid whose major constituents are water and one or more glycols.
Water Hammer
Banging of pipes caused by the shock of closing valves - eg taps.
Water Hardening
High carbon grades of tool steel, straight carbon steels and low alloy steels that are hardened by quenching in water during the heat treating operation.
Water Hardness
Water contaminated with compounds of calcium and magnesium.
Water Jacket
The outer casing forming a space around an engine cylinder to permit circulation of cooling water.
Water Jet
High-pressure stream of water used for cutting.
Water Lubricant
Water used as a lubricant.
Water of Crystallization
Water present in the crystal of a hydrate.
Water of Rabel
A solution of ethyl ether in ethanol.
Water Softener
A device or system used to remove calcium and magnesium hardness minerals from a water supply.
Water Tube
A boiler tube through which the fluid under pressure flows.
Water Tube Boiler
A boiler whose primary heating surface is composed of many small tubes, filled with water.
Water Vapour
Water in gaeous form.
Water Wall
A furnace or other wall within a boiler enclosure that is composed of numerous closely set water tubes.
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.
The line of the water′s edge when the ship is afloat.
A wheel with paddles designed to extract power from flowing water.
The watt is the SI unit of power and is equal to 1 joule per second.
Watt Hour
A unit of energy equivalent to one watt of power expended for one hour of time.
Watt Hour Meter
A meter used to measure electrical energy.
Watt Hours per Kilogram
Unit of energy density.
Watt, James
He made fundamental improvements in the steam engine, resulting in the modern, high-pressure steam engine, patented in 1769.
Wattage Rating
A rating expressing the maximum power that a device can safely handle.
Watt-hour Efficiency
This the energy out of a battery during discharge divided by the energy in during charging.
A meter used to measure electrical power.
Watts Link
Lateral locating device for a solid axle.
The movement of energy from one place to another without any accompanying matter.
Wave Antenna
Same as a Beverage Antenna.
Wave Equation
The wave equation describes the propagation of waves.
Wave Interference
The resultant when waves of the same or nearly the same frequency are superposed.
Wave Motion
A recurring disturbance advancing through space with or without the use of a physical medium.
Wave Particle Duality
The observation that electrons; photons; and other very small entities behave like particles in some experiments and like waves in others.
Wave Phenomena
The characteristics of radiant energy.
Wave Train
A continuous series of waves with the same amplitude and wavelength.
Wave Winding
An armature winding in which the two ends of each coil are connected to commutator segments separated by the distance between poles.
A series of wavelengths forming a group.
The shape of a time domain signal as seen on an oscilloscope screen.
Waveform Analysis
Observation displays of voltage and current variations with respect to time or by harmonic analysis of complex signals.
A set of points at which the phase of vibration of the physical quantity associated with a wave is the same.
Wavefront Deformation
Departure of a wavefront from ideal (usually spherical or planar) caused by surface errors or design limitations.
A mathematical function that gives the amplitude of a wave as a function of position.
A rectangular, circular, or elliptical metal pipe designed to transport electromagnetic waves through its interior.
Waveguide Mode of Operation
Any particular field configuration in a waveguide that satisfies the boundary conditions.
Waveguide Post
A rod of conductive material used as impedance changing devices in waveguides.
Waveguide Screw
A screw that projects into a waveguide for the purpose of changing the impedance.
The shortest repetition length for a periodic wave.
Wavelength Dispersion
Dispersion cause by the dependence of the phase and group velocities on wavelength due to geometric properties of the waveguide.
The wavelet allows a rapidly changing time history (e.g. door slam noise) to be investigated in the frequency domain.
An instrument for measuring the wavelength of an RF wave.
An instrument for measuring the frequency of a radio wave.
Wavenumber describes the spatial variation of waves, phase change per unit distance.
Esters of monohydric alcohols.
Longitudinal surface that guides the reciprocal movement of a machine part.