[n] the act of causing something to move up and down (or back and forth) with quick movements
[n] a shaky motion; "the shaking of his fingers as he lit his pipe"
[adj] vibrating slightly and irregularly; as e.g. with fear or cold or like the leaves of an aspen in a breeze; "a quaking bog"; "the quaking child asked for more"; "quivering leaves of a poplar tree"; "with shaking knees"; "seemed shaky on her feet"; "sparkling light from the shivering crystals of the chandelier"; "trembling hands"
Synonyms
palpitation, quaking, quiver, quivering, quivering, shakiness, shaky, shivering, trembling, trembling, unsteady, vibration