To coo is to speak softly and gently, or make the soft sound of a bird.(verb)
The definition of a coo is the sound of a bird.(noun)
An example of a coo is the sound of a Mourning Dove.
See coo in Webster's New World College Dictionary
See coo in American Heritage Dictionary 4
verb cooed, coo·ing, Coos coos verb, intransitive
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