'Tanystomata' definitions:

Definition of 'Tanystomata'

From: GCIDE

Tanystomata \Tan`y*stom"a*ta\, n. pl. [NL., fr. Gr. ? to stretch + ?, ?, mouth.] (Zool.) A division of dipterous insects in which the proboscis is large and contains lancelike mandibles and maxillae. The horseflies and robber flies are examples. [1913 Webster]