Barnum play biographical name Bar·num \ˈbär-nəm\ Definition of Barnum Phineas Taylor 1810–1891 Am. showmanBarnumesque play \ˌbär-nə-ˈmesk\ adjective See words that rhyme with Barnum Writing? Check your grammar now! Seen and Heard What made you want to look up Barnum? Please tell us where you read or heard it (including the quote, if possible).