n pl :  a large order of winged or rarely wingless insects that have the anterior wings usu. functional and the posterior wings reduced to small club-shaped structures functioning as sensory flight stabilizers, that have a segmented larva often without a head, eyes, or legs, and that include the true flies (as the housefly, mosquitoes, midges, and gnats) .
 
 
 
Similar sounding terms:  di·op·ter 
 
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