Per`tur*ba"tion (?), n. [L. perturbatio: cf. F. perturbation.] 1. The
act of perturbing, or the state of being perturbed; esp., agitation of
mind.
2. (Astron.) A disturbance in the regular elliptic or other motion of a
heavenly body, produced by some force additional to that which causes
its regular motion; as, the perturbations of the planets are caused by
their attraction on each other. Newcomb.
Per`tur*ba"tion*al (?), a. Of or pertaining to perturbation, esp. to
the perturbations of the planets. "The perturbational theory." Sir J.
Herschel.
Per"tur*ba*tive (?), a. Tending to cause perturbation; disturbing. Sir
J. Herschel.