A large falcon (Falco rusticolus) of Arctic areas, having shade stages that consist of black to gray to white.
Any huge falcon, particularly as accustomed travel at herons.
a sizable bird of victim that breeds on Arctic coasts and countries of the united states, Europe and Asia.
One of several types and kinds of big Arctic falcons, esp. Falco rusticolus and also the white types Falco Islandicus, both of that are circumpolar. The black as well as the gray tend to be types of the previous. See Illust. of accipiter.
big and rare Arctic falcon having white and dark shade stages