motion the act of changing location from one place to another; "police controlled the motion of the crowd"; "the movement of people from the farms to the cities"; "his move put him directly in my path"
tremolo vocal vibrato especially an excessive or poorly controlled one
shaking -
the act of causing something to move up and down (or back and forth) with quick movements
agitation the act of agitating something; causing it to move around (usually vigorously)
