palpitation palpitation /ˌpælpəˈteɪʃən/

noun

1. A shaky motion  ( palpitation , quiver , quivering , shakiness , shaking , trembling , vibration )
   a shaky motion
    The shaking of his fingers as he lit his pipe
   the shaking of his fingers as he lit his pipe
   
2. A rapid and irregular heart beat  ( palpitation )
   a rapid and irregular heart beat