Synonyms: shaking
Definition: the act of causing something to move up and down (or back and forth) with quick movements
Similar words: agitation
Definition: the act of agitating something; causing it to move around (usually vigorously)
Synonyms: palpitation, trembling, quiver, quivering, shakiness, shaking, vibration
Definition: a shaky motion
Usage: the shaking of his fingers as he lit his pipe