The Collaborative International Dictionary of English v.0.48:

Tetraonid \Te*tra"o*nid\, n. [L. tetrao a heath cock, grouse,
   Gr. ?: cf. F. t['e]traonide.] (Zool.)
   A bird belonging to the tribe of which the genus Tetrao is
   the type, as the grouse, partridge, quail, and the like. Used
   also adjectively.
   [1913 Webster]