or K.O., k.o., kay·o
[noun key-oh, key-oh; verb key-oh]Slang.
- a knockout in boxing.
- to knock unconscious, especially in a boxing match; knock out.
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. 2018
- a slang term for knock outSee knockout
- 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