a part of an axle or shaft bent at right angles by which reciprocating motion is changed into circular motion or vice versa

an eccentric person, or one who is excessively enthusiastic or fastidious about something

The man with a new idea is a crank until the idea succeeds — Mark Twain

(often + up) to turn a crank, or to start (an engine) using a crank

(+ up) to increase (something, e.g. the volume of a sound) in intensity

to bend (a shaft, etc) into the shape of a crank

to turn a crank, e.g. to start an engine

informal to inject a narcotic drug