verb (used without object), cooed, coo·ing.

to utter or imitate the soft, murmuring sound characteristic of doves.
to murmur or talk fondly or amorously.

verb (used with object), cooed, coo·ing.

to utter by cooing.


a cooing sound.

Origin of coo

First recorded in 1660–70; imitative
Related formscoo·er, nouncoo·ing·ly, adverb



interjection British Slang.

(used to express surprise or amazement.)

Origin of coo

First recorded in 1910–15; origin uncertain




Italian name of Kos.


chief operating officer. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for coo

murmur, sound, utter, woo

Examples from the Web for coo

Contemporary Examples of coo

Historical Examples of coo

  • When she is called for—says the story—the puppets in the four corners begin to coo.

    Russian Fairy Tales

    W. R. S. Ralston

  • Presently there came the “coo” of a wood-pigeon from in front.

    Danger! and Other Stories

    Arthur Conan Doyle

  • Something between the 'gobble, gobble' of a turkey and the coo of the ring-dove.

  • He did not “coo” as usual, but stared unsmilingly at the ceiling.

    The Cheerful Smugglers

    Ellis Parker Butler

  • I know all the birds say when they twitter and chirp, caw and coo, gobble and cluck.

    Europa's Fairy Book

    Joseph Jacobs

British Dictionary definitions for coo


verb coos, cooing or cooed

(intr) (of doves, pigeons, etc) to make a characteristic soft throaty call
(tr) to speak in a soft murmur
(intr) to murmur lovingly (esp in the phrase bill and coo)


the sound of cooing


British slang an exclamation of surprise, awe, etc
Derived Formscooer, nouncooingly, adverb


abbreviation for

cost of ownership


abbreviation for

chief operating officer
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

Word Origin and History for coo

1660s, echoic of doves; the phrase to bill and coo is first recorded 1816. Related: Cooing. The noun is recorded from 1729.

Online Etymology Dictionary, © 2010 Douglas Harper