gyrfalcon
Concise Oxford English Dictionary © 2008 Oxford University Press:
gyrfalcon /ˈdʒəːˌfɔː(l)k(ə)n, -ˌfɒlk(ə)n/
▶noun a large arctic falcon, occurring in several colour forms including a mainly white one. [Falco rusticolus.]
– origin ME: from OFr. gerfaucon, of Gmc origin, prob. rel. to Old High Ger. gēr ‘spear’.
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