Oxford Dictionary English best man nounnoun BrE BrE//ˌbest ˈmæn// ; NAmE NAmE//ˌbest ˈmæn// [singular] Marriage Add to my wordlistjump to other resultsa male friend or relative of the bridegroom at a wedding, who helps him during the wedding ceremony compare bridesmaid Wordfinderweddingbest man, bride, ceremony, engaged, honeymoon, marriage, propose, reception, stag night, wedding See related entries: MarriageSee best man in the Oxford Advanced American DictionaryCheck pronunciation: best man oxfordlearnersdictionaries.com