noun

• (dated) A carnival performer specializing in bizarre and unappetizing behavior.
  "I once saw a geek bite the head off a live chicken."
• (colloquial) 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.
  "I was a complete computer geek in high school, but I get out a lot more now."
• (colloquial, by extension) An expert in a technical field, particularly one having to do with computers.
  "My laptop’s locked up again. I need a geek."
• (uncountable, colloquial) 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.
  "It is totally counter-intuitive. How do these ubernerds get the cute girls? Is it the ultimate triumph of the Bill Gates era, in which geek is the new cool?"

verb

• (intransitive) To perform bizarre and unpleasant feats as part of a carnival.
  "Geeking, unsurprisingly, was among the first carnival acts to be outlawed as the 20th century unfurled."
• (intransitive, colloquial) To enthusiastically engage in geek-like or nerdy interests.
  "It was our first time at a Star Trek convention and we had an amazing time wandering around and geeking."
• (intransitive, African-American Vernacular, slang) To be nervous or hyperactive due to using crack cocaine.
  "I ain't nothin' but a clucker, your typical glass dick suckin' basehead, geekin' motherfucker"
• (intransitive, African-American Vernacular, slang) To be nervous or hyperactive due to using crack cocaine.

noun

• (Australia, colloquial) A look.
  "Have a geek at this."

verb

• (Cornwall) To look; to peep; to stare about intently.
  "This gayte bucca-davy, all'ys geekin' round arter a gook."