Source : Webster's Revised Unabridged Dictionary (1913)

Aptera \Ap"te*ra\, n. pl. [NL. aptera, fr. Gr. ? without wings;
   'a priv. + ? wing, ? to fly.] (Zo["o]l.)
   Insects without wings, constituting the seventh Linn[ae]n
   order of insects, an artificial group, which included
   Crustacea, spiders, centipeds, and even worms. These animals
   are now placed in several distinct classes and orders.