an unofficial title held by a horse that wins the Kentucky Derby, the Preakness, and the Belmont Stakes in a single season.
a usually unofficial title held by someone who wins three major awards or championships in the same year.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
RC Church the Pope's tiara
horse racing the winning of three important races in one season
(often capitals) rugby Union a victory by Scotland, England, Wales, or Ireland in all three games against the others in the annual Six (formerly, Five) Nations ChampionshipCompare grand slam (def. 3)
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