Lewis & Short

quassātĭo, ōnis, f. [quasso],

  1. I. a shaking: capitum, Liv. 22, 17, 3: cymbalorum, a striking together, beating, Arn. 7, 237: quassationes, shakings of the body, Macr. S. 7, 15, 9.
  2. II. A disturbance, affliction: cessavit quassatio, Vulg. Psa. 105, 30.