Falcon :: Falcon (n.) One of a family (Falconidae) of raptorial birds, characterized by a short, hooked beak, strong claws, and powerful flight..
Falcon :: Falcon (n.) Any species of the genus Falco, distinguished by having a toothlike lobe on the upper mandible; especially, one of this genus trained to the pursuit of other birds, or game..
Gyrfalcon :: Gyrfalcon (n.) One of several species and varieties of large Arctic falcons, esp. Falco rusticolus and the white species F. Islandicus, both of which are circumpolar. The black and the gray are varieties of the former. See Illust. of Accipiter..