or K.O., k.o., kay·o
[ noun key-oh, key-oh; verb key-oh ]
/ noun ˈkeɪˈoʊ, ˈkeɪˌoʊ; verb ˈkeɪˈoʊ /
noun, plural KO's.
a knockout in boxing.
verb (used with object), KO'd, KO'ing.
to knock unconscious, especially in a boxing match; knock out.
Can You Ace This Quiz About “Compliment” vs. “Complement”?
Take this quiz to see if you really know the difference between “compliment” and “complement"!
Question 1 of 11
“Compliment” and “complement” had a shared meaning a long time ago, but today they are no longer interchangeable.
Origin of KO
First recorded in 1920–25; initial letters of knock out
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
British Dictionary definitions for koing
/ (ˈkeɪˈəʊ) /
verb KO's, KO'ing, KO'd, k.o.'s, k.o.'ing or k.o.'d
a slang term for knock outSee knockout
noun plural KO's or k.o.'s
a slang term for knockout
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