1. audacity Audacity, in the sense here considered, is a reckless defiance of law, decency, public opinion, or personal rights, claims, or views, approaching the meaning of impudence or shamelessness, but Synonyms: effrontery, assurance, boldness, hardihood, insolence, audacity, brass, impudence, shamelessness Antonyms: bashfulness, diffidence, sensitiveness, shyness, coyness, modesty, shrinking, timidity