The Collaborative International Dictionary of English v.0.48:

Bipennate \Bi*pen"nate\, Bipennated \Bi*pen"na*ted\, a. [Pref.
   bi- + pennate: cf. L. bipennis. Cf. Bipinnate.]
   Having two wings. "Bipennated insects." --Derham.
   [1913 Webster]