romper Syllabification: (romp·er)Pronunciation: /ˈrämpər, ˈrôm-/Entry from US DictionaryDefinition of romper noun 1 (also romper suit or rompers) a young child’s one-piece outer garment. a garment for adults similar to a romper, typically worn as overalls or as sports clothing. 2a person who romps. romper in other Oxford dictionaries Definition of romper in the US English dictionary