geek

Short definition from Wiktionary

Noun

1. 1
   A carnival performer specializing in bizarre and unappetizing behavior.
2. 2
   A person who is intensely interested in a particular field or hobby and often having limited or nonstandard social skills. Often used with an attributive noun.
3. 3
   An expert in a technical field, particularly one having to do with computers.
4. 4
   The subculture of geeks; an esoteric subject of interest that is marginal to the social mainstream; the philosophy, events, and physical artifacts of geeks; geekness.
5. 5
   An unfashionable or socially undesirable person.
6. 6
   A look.

Verb

1. 1
   To perform bizarre and unpleasant feats as part of a carnival.
2. 2
   To enthusiastically engage in geek-like or nerdy interests.
3. 3
   To be nervous or hyperactive due to using crack cocaine.
4. 4
   To be nervous or hyperactive due to using crack cocaine: To be under the influence of a mood-altering drug.
5. 5
   To look; to peep; to stare about intently.