operant

from WordNet (r) 3.0 (2006)

operant
    adj 1: having influence or producing an effect; "many emotional
           determinants at work"; "an operant conscience"

from The Collaborative International Dictionary of English v.0.48

Operant \Op"er*ant\, a. [L. operans, p. pr. of operari. See
   {Operate}.]
   Operative. [R.] --Shak. -- n. An operative person or thing.
   [R.] --Coleridge.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

31 Moby Thesaurus words for "operant":
      actor, agent, architect, author, conductor, creator, doer, driver,
      engineer, executant, executor, executrix, fabricator, functionary,
      handler, maker, manipulator, medium, mover, operative, operator,
      performer, perpetrator, pilot, practitioner, prime mover, producer,
      runner, steersman, subject, worker

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