pseudo
     adj : (often used in combination) not genuine but having the
           appearance of; "a pseudo esthete"; "pseudoclassic"
     n : a person who makes deceitful pretenses [syn: {imposter}, {impostor},
          {pretender}, {fake}, {faker}, {fraud}, {sham}, {shammer},
          {pseud}, {role player}]
Source: WordNet® 2.0

pseudo /soo'doh/ n. [Usenet: truncation of `pseudonym'] 1. An
   electronic-mail or {Usenet} persona adopted by a human for amusement
   value or as a means of avoiding negative repercussions of one's
   net.behavior; a `nom de Usenet', often associated with forged postings
   designed to conceal message origins. Perhaps the best-known and funniest
   hoax of this type is {B1FF}. See also {tentacle}. 2. Notionally, a
   {flamage}-generating AI program simulating a Usenet user. Many flamers
   have been accused of actually being such entities, despite the fact that
   no AI program of the required sophistication yet exists. However, in
   1989 there was a famous series of forged postings that used a
   phrase-frequency-based travesty generator to simulate the styles of
   several well-known flamers; it was based on large samples of their back
   postings (compare {Dissociated Press}). A significant number of people
   were fooled by the forgeries, and the debate over their authenticity was
   settled only when the perpetrator came forward to publicly admit the
   hoax.


Source: The Jargon File