reserve
That which is reserved or kept back, as for future use.
Entries starting with R
282 entries.
resettable fuse
A passive electronic component used to protect against overcurrent faults in circuits.
residual-current device
An automatic circuit breaker that rapidly disconnects an electric circuit when the imbalance of the currents going through it exceeds a specific value.
resistance distance
In classical mechanics, the distance from the resistance (on a lever) to the fulcrum.
resistivity
The resistance offered at a particular temperature by an electrical conductor of any given material in a cube of unit length, expressed in ohm-metres (Ωm) in the metric system of measurement.
resistor
An electric component that transmits current in direct proportion to the voltage across it.
resmelt
verbMetallurgy
To smelt again; to smelt a second time.
response time
The time taken for the display of an instrument to move to a new value following a step change.
responsor
A receiver used in conjunction with an interrogator to receive and interpret signals from a transponder.
respot
nounManufacturing
The final welding on a manufactured item.
retaining valve
A device that retains some air pressure in a train's air brake cylinders even when the automatic brake valve is set to the fully-released position, used on steep downgrades to allow a degree of continuous braking effort to be maintained without depleting the pressure in the train's brakepipe (which would result in the loss of nearly all braking ability, causing a runaway).
retarded time
The time when the field begins to propagate from the point where it is emitted to an observer.
retarder
A device for slowing down large trucks, lorries, buses, shunted railway wagons.
return
A roadway along which foul air travels from the face on its way out of the mine.
return current
The electric current in a circuit which flows back to its source, or to earth.
return flow
Surface or subsurface water that leaves the field following application of irrigation water.
return path
The route by which a current or signal returns to its source, or to earth.
return spring
The spring that returns a door handle or knob to its original position when rotated.
REV
nounAutomotive
Initialism of range-extended vehicle or range extender vehicle
rev st st
Abbreviation of reverse stocking stitch; reverse stockinette stitch.
reverberate
To heat something by deflecting flames on to, or passing flames over, it.
reverse gear
A gear (setting) in a vehicle's transmission which, when selected, makes the vehicle move backward. (Denoted with symbol R on a shifter's labeling.)
reverse intaglio
A design impressed into the back of transparent or translucent items.
reverse link
In radio communications, the link from a mobile user to a fixed base station. If the link includes a communications relay satellite, the reverse link will consist of both an uplink (mobile station to satellite) and a downlink (satellite to base station).
reverse out
To print with reversed colours, i.e. black for white and vice versa.
rework
nounManufacturing
Taking unsaleable food and using it in the manufacture of other food.
RFFE
Initialism of radio frequency front end.
RFID
Initialism of radio-frequency identification.
RH
nounManufacturing
Initialism of right hand.
rheostat
An electrical resistor with two terminals, the resistance of which can be varied continuously by moving a knob or slider to regulate the flow of an electric current.
RHS
nounConstruction
Initialism of rectangular hollow section.
RHU
nounRobotics
Initialism of radioisotope heater unit, a device that generates heat from the natural decay of radioactive material.
rib
nounManufacturing
A raised ridge in knitted material or in cloth.
ribband
nounManufacturing
A long, narrow strip of timber bent and bolted longitudinally to the ribs of a vessel, to hold them in position and give rigidity to the framework.
RICE
Acronym of reciprocating internal combustion engine.
ridge beam
nounCarpentry
The top longitudinal beam of a ridged roof where the top ends of the rafters meet.
ridge course
nounConstruction
The last or top course of roofing materials, such as tile, roll roofing, shingles, etc. that covers the ridge and overlaps the intersecting field roofing.
ridge tile
nounConstruction
A curved or bent tile specifically designed to cover the apex or ridge of a pitched roof, where two roof planes converge.
ridge vent
nounConstruction
A vent located at the ridge of the roof that allows the escape of warm and/or moist air from the attic area or rafter cavity; it is usually a simple shielded gap but may be a ventilator (device).
riffle
A trough or sluice having cleats, grooves, or steps across the bottom for holding quicksilver and catching particles of gold when auriferous earth is washed. Also one of the cleats, grooves or steps in such trough.
rig
verbManufacturing
To fit out with a harness or other equipment.
right side
The side of a fabric, often with a more visible color or pattern, that is intended to face outward on a finished project.
right-away signal
nounRail equipment
A signal given to a train driver by the guard of the train, or a member of station staff, that the train is ready to depart.
right-hander
nounAutomotive
A bend or turn to the right; a right-hand corner.
rind grafting
A technique used to join a small scion onto the end of a thicker rootstock by inserting it under the lifted bark or rind.
ring cadence
The ringing pattern heard by the dialer before the called party picks up the call.
ring modulation
A signal processing function in which two signals (typically a complex signal and a less complex carrier such as a sine wave) are combined to yield an output.
ring spinner
A machine for spinning, in which the twist, given to the yarn by a revolving bobbin, is regulated by the drag of a small metal loop which slides around a ring encircling the bobbin, instead of by a throstle.
ring time
The duration of time from the moment that the respondent's telephone begins ringing until the moment it is answered.
ringer equivalence number
A number denoting the electrical load of a telephone ringer circuit on a particular line.
ringhead
nounWoodworking
A cutting tool or assembly that consists of a circular head which houses multiple cutting knives or blades arranged in a ring formation.
rip
verbWoodworking
To cut wood along (parallel to) the grain.
ripper
A tool or plant used to reduce soil compaction.
ripping
nounCarpentry
The action of one who rips (in any sense).
ripple
nounManufacturing
An implement, with teeth like those of a comb, for removing the seeds and seed vessels from flax, broom corn, etc.
ripsaw
nounWoodworking
A saw that is designed to cut wood along its grain, i.e. to rip, to execute a rip cut.
rise time
Of a voltage or current step function, the amount of time taken by a signal to change from a specified low value to a specified high value.
riser
nounCarpentry
A vertical part of a step on a staircase.
rive
verbCarpentry
To use a technique of splitting or sawing wood radially from a log (e.g. clapboards).
riveter
nounMetallurgy
A person whose job is to rivet.