simple past tense and past participle of retain

Third-person singular simple present indicative form of retain

The quality of being retainable.

plural of retainer

to continue to have or use something; to keep

plural of retaining wall

(rail transport, mechanical engineering) 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).

plural of retaining valve

Any of several structures used to restrain a vertical-faced mass of earth.

(computer graphics) A mode in which the application updates a set of graphical objects which are stored and displayed by the graphics library, contrasting with immediate mode.