The definition of a bird is a warm blooded member of the Aves class, which has feathers, a beak, no teeth, wings and bears young in eggs.(noun)
An example of bird is a robin.
See bird in Webster's New World College Dictionary
Origin: ME bird, brid < OE bridd, bird, orig., young bird
See bird in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English brid, young bird.
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