- noun a sudden movement of part of the body which indicates that the local reflex arc is intact
- verb to make sudden movements, or cause something to make sudden movements
- noun a foolish, despicable or obnoxious person. This American term crossed over into limited British usage during and after World War II. It is usually pejorative, although it is sometimes used with pitying or even affectionate connotations in American speech. The word seems to derive from jerk off, meaning to masturbate, and was probably originally a rural term for an idle or immature boy.