Source : Webster's Revised Unabridged Dictionary (1913)

Hornet \Hor"net\, n. [AS. hyrnet; akin to OHG. hornaz, hornuz,
   G. horniss; perh. akin to E. horn, and named from the sound
   it makes as if blowing the horn; but more prob. akin to D.
   horzel, Lith. szirszone, L. crabo.] (Zo["o]l.)
   A large, strong wasp. The European species ({Vespa crabro})
   is of a dark brown and yellow color. It is very pugnacious,
   and its sting is very severe. Its nest is constructed of a
   paperlike material, and the layers of comb are hung together
   by columns. The American white-faced hornet ({V. maculata})
   is larger and has similar habits.

   {Hornet fly} (Zo["o]l.), any dipterous insect of the genus
      {Asilus}, and allied genera, of which there are numerous
      species. They are large and fierce flies which capture
      bees and other insects, often larger than themselves, and
      suck their blood. Called also {hawk fly}, {robber fly}.

   {To stir up a hornet's nest}, to provoke the attack of a
      swarm of spiteful enemies or spirited critics. [Colloq.]

Source : WordNet®

Vespa crabro
     n : European hornet introduced into the United States [syn: {giant
         hornet}]