nerd
     n : an insignificant student who is ridiculed as being affected
         or studying excessively [syn: {swot}, {grind}, {wonk}, {dweeb}]
Source: WordNet® 2.0

nerd n. 1. [mainstream slang] Pejorative applied to anyone with an
   above-average IQ and few gifts at small talk and ordinary social
   rituals. 2. [jargon] Term of praise applied (in conscious ironic
   reference to sense 1) to someone who knows what's really important and
   interesting and doesn't care to be distracted by trivial chatter and
   silly status games. Compare {geek}.

   The word itself appears to derive from the lines "And then, just to
   show them, I'll sail to Ka-Troo / And Bring Back an It-Kutch, a Preep
   and a Proo, / A Nerkle, a Nerd, and a Seersucker, too!" in the Dr. Seuss
   book "If I Ran the Zoo" (1950). (The spellings `nurd' and `gnurd' also
   used to be current at MIT, where `nurd' is reported from as far back as
   1957.) How it developed its mainstream meaning is unclear, but sense 1
   seems to have entered mass culture in the early 1970s (there are reports
   that in the mid-1960s it meant roughly "annoying misfit" without the
   connotation of intelligence).

   An IEEE Spectrum article (4/95, page 16) once derived `nerd' in its
   variant form `knurd' from the word `drunk' backwards, but this bears all
   the hallmarks of a bogus folk etymology.

   Hackers developed sense 2 in self-defense perhaps ten years later, and
   some actually wear "Nerd Pride" buttons, only half as a joke. At MIT one
   can find not only buttons but (what else?) pocket protectors bearing the
   slogan and the MIT seal.


Source: The Jargon File