The Collaborative International Dictionary of English v.0.48:

Pretender \Pre*tend"er\, n.
   1. One who lays claim, or asserts a title (to something); a
      claimant. Specifically, The pretender (Eng. Hist.), the
      son or the grandson of James II., the heir of the royal
      family of Stuart, who laid claim to the throne of Great
      Britain, from which the house was excluded by law.
      [1913 Webster]

            It is the shallow, unimproved intellects that are
            the confident pretenders to certainty. --Glanvill.
      [1913 Webster]

   2. One who pretends, simulates, or feigns.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Pretender
    n 1: a claimant to the throne or to the office of ruler (usually
         without just title)
    2: a person who makes deceitful pretenses [syn: imposter,
       impostor, pretender, fake, faker, fraud, sham,
       shammer, pseudo, pseud, role player]
    3: a person who professes beliefs and opinions that he or she
       does not hold in order to conceal his or her real feelings or
       motives [syn: hypocrite, dissembler, dissimulator,
       phony, phoney, pretender]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "pretender":
   actor, affecter, arrogator, aspirant, blagueur, bluff, bluffer,
   candidate, charlatan, claimant, deceiver, fake, faker, fourflusher,
   fraud, hollow man, humbug, impersonator, impostor, malingerer,
   man of straw, mannerist, mountebank, paper tiger, performer, phony,
   playactor, poser, poseur, quack, quacksalver, quackster, ringer,
   rival, saltimbanco, seeker, sham, shammer, straw man, suitor,
   usurper