yellow-bellyEnglishOxford New American Dictionaryyellow-belly /ˈyelō ˌbelē, ˈjɛloʊ ˌbɛli / ▸ noun 1 informal, derogatory a cowardly person; a coward: I was serious about my stand against the war and was not just a yellow-belly. 2 any of various animals with yellow underparts. – DERIVATIVES yellow-bellied /ˈyelō ˌbelēd, ˈjɛloʊ ˌbɛlid/ adjective