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definitions

bastard wing

noun Ornithology.

alula(def 1).

Origin of bastard wing

First recorded in 1765–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for bastard wing

bastard wing

noun

a tuft of feathers attached to the first digit of a bird, distinct from the wing feathers attached to the other digits and the ulnaAlso called: alula
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