\Con*tract"ile\, a. [Cf. F. contractile.]
tending to contract; having the power or property of
contracting, or of shrinking into shorter or smaller
dimensions; as, the contractile tissues.
      The heart's contractile force.           --H. Brooke.
      Each cilium seems to be composed of contractile
      substance.                               --Hixley.
{Contractile vacuole} (Zo["o]l.), a pulsating cavity in the
   interior of a protozoan, supposed to be excretory in
   function. There may be one, two, or more.