[uh, oh]

Origin of o'

Middle English; by shortening.


  1. a prefix meaning “descendant,” in Irish family names: O'Brien; O'Connor.

Origin of O'

representing Irish ó descendant, Old Irish au
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for o'


  1. informal, or archaic shortened form of of a cup o' tea
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 o'


as a prefix in Irish names, from Irish ó, ua (Old Irish au) "descendant."

Online Etymology Dictionary, © 2010 Douglas Harper