The Collaborative International Dictionary of English v.0.48:

Geococcyx \Geococcyx\ n.
   The genus of birds comprising the roadrunners.

   Syn: genus Geococcyx.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Geococcyx
    n 1: roadrunners [syn: Geococcyx, genus Geococcyx]