The Collaborative International Dictionary of English v.0.48:

Counterfeiter \Coun"ter*feit`er\ (-f?t`?r), n.
   1. One who counterfeits; one who copies or imitates;
      especially, one who copies or forges bank notes or coin; a
      forger.
      [1913 Webster]

            The coin which was corrupted by counterfeiters.
                                                  --Camden.
      [1913 Webster]

   2. One who assumes a false appearance or semblance; one who
      makes false pretenses.
      [1913 Webster]

            Counterfeiters of devotion.           --Sherwood.
      [1913 Webster]

WordNet (r) 3.0 (2006):

counterfeiter
    n 1: someone who makes copies illegally [syn: forger,
         counterfeiter]

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "counterfeiter":
   Artful Dodger, Casanova, Don Juan, Machiavel, Machiavelli,
   Machiavellian, actor, ape, bamboozler, befuddler, beguiler,
   charmer, coin-clipper, coiner, conformist, copier, copycat,
   copyist, cuckoo, deceiver, deluder, dissembler, dissimulator,
   dodger, double-dealer, duper, echo, echoer, echoist, enchanter,
   entrancer, faker, fooler, forger, gay deceiver, hoaxer, hypnotizer,
   hypocrite, imitator, impersonator, impostor, jilt, jilter, joker,
   jokester, kidder, leg-puller, mesmerizer, mime, mimer, mimic,
   mimicker, minter, mintmaster, misleader, mocker, mockingbird,
   moneyer, monkey, parrot, phony, plagiarist, plagiarizer, playactor,
   poll-parrot, polly, polly-parrot, poseur, practical joker, ragger,
   role-player, seducer, sheep, simulator, spoofer, tease, teaser