gadfly

  1. Noun.  Any dipterous insect of the genus Oestrus, and allied group of botflies.
  2. Noun.  A horsefly: any of various species of fly, of the family Tabanid[ae], noted for buzzing about animals and sucking their blood.
  3. Noun.  One who upsets the status quo by posing upsetting or novel questions, or attempts to stimulate innovation by proving an irritant.
  4. Noun.  (pejorative) One who merely irritates without making useful suggestions.
  5. Noun.  (slang) A bloodsucker.

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This entry was last updated on RefTopia from its source on 3/20/2012.