dastardly

having or showing a shameful lack of courage his dastardly conduct in a critical moment haunted him for the rest of his life Synonyms chicken, chickenhearted, chicken-livered, craven, cowardly, gutless, lily-livered, milk-livered [archaic], poltroon, pusillanimous, recreant, spineless, unheroic, yellowRelated Words diffident, fainthearted, fearful, timid, timorous; afraid, frightened, scared; careful, cautious, wary; bashful, coy, shy; feeble, soft, unmanly, weakNear Antonyms audacious, bold, brazen, cheeky, nervy; plucky, spirited, spunky; determined, resoluteAntonyms brave, courageous, daring, dauntless, doughty, fearless, gallant, greathearted, gutsy, hardy, heroic (also heroical), intrepid, lionhearted, stalwart, stout, stouthearted, valiant, valorous