shaking
     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" [syn: {quaking}, {quivering}, {shaky},
            {shivering}, {trembling}]
     n 1: the act of causing something to move up and down (or back
          and forth) with quick movements
     2: a shaky motion; "the shaking of his fingers as he lit his
        pipe" [syn: {shakiness}, {trembling}, {quiver}, {quivering},
         {vibration}, {palpitation}]
Source: WordNet® 2.0