contractile
    adj 1: capable of contracting or being contracted; "the
           contractile wings of an insect"

Contractile \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.
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         The heart's contractile force.           --H. Brooke.
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         Each cilium seems to be composed of contractile
         substance.                               --Hixley.
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   Contractile vacuole (Zool.), a pulsating cavity in the
      interior of a protozoan, supposed to be excretory in
      function. There may be one, two, or more.
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