Convulsion /(?)/

Con·vul·sion

Convulsion

n.
  1. An unnatural, violent, and unvoluntary contraction of the muscular parts of an animal body. (Med.)
  2. Any violent and irregular motion or agitation; a violent shaking; a tumult; a commotion.
    Those two massy pillars, With horrible convulsion, to and fro He tugged, he shook, till down they came.
    Times of violence and convulsion.
    — Ames.