Bluebottle

from WordNet (r) 3.0 (2006)

bluebottle
    n 1: an annual Eurasian plant cultivated in North America having
         showy heads of blue or purple or pink or white flowers
         [syn: {cornflower}, {bachelor's button}, {bluebottle},
         {Centaurea cyanus}]
    2: blowfly with iridescent blue body; makes a loud buzzing noise
       in flight [syn: {bluebottle}, {Calliphora vicina}]

from The Collaborative International Dictionary of English v.0.48

Bluebottle \Blue"bot`tle\, blue-bottle \blue-bottle\, n.
   1. (Bot.) an annual Eurasian plant ({Centaurea cyanus}) which
      grows in grain fields; -- called also {bachelor's button}.
      It receives its name from its blue bottle-shaped flowers.
      Varieties cultivated in North America have showy heads of
      blue or purple or pink or white flowers

   Syn: cornflower, bachelor's button.
        [1913 Webster + WordNet 1.5]

   2. (Zool.) A large and troublesome species of blowfly ({Musca
      vomitoria}). Its body is steel blue.
      [1913 Webster]