gutless adj. + Add to list US //ˈɡətɫɛs// UK //ɡˈʌtləs// gut·less Informal SynonymsAntonymsEtymology Synonyms namby pambyspinelesswishy washy Antonyms gutsyOrigin From gut + -less. Idioms1 entry01gutless wonderOne who lacks guts or courage; a coward.