Source : Webster's Revised Unabridged Dictionary (1913)

Dipteran \Dip"ter*an\, n. (Zo["o]l.)
   An insect of the order Diptera.

Source : WordNet®

dipteran
     n : insects having usually a single pair of functional wings
         (anterior pair) with the posterior pair reduced to small
         knobbed structures and mouth parts adapted for sucking or
         lapping or piercing [syn: {dipterous insect}, {two-winged
         insects}, {dipteron}]