- to utter or imitate the soft, murmuring sound characteristic of doves.
- to murmur or talk fondly or amorously.
- to utter by cooing.
- a cooing sound.
Origin of coo1
First recorded in 1660–70; imitative
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- (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
- cost of ownership
- 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
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