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wing bow

American  
[boh] / boʊ /

noun

  1. the distinctively colored feathers on the shoulder or bend of the wing of a bird.


wing bow British  
/ bəʊ /

noun

  1. a distinctive band of colour marking the wing of a bird

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of wing bow

First recorded in 1865–70