Oxford Dictionary English Freudian slip nounnoun BrE BrE//ˌfrɔɪdiən ˈslɪp// ; NAmE NAmE//ˌfrɔɪdiən ˈslɪp// Add to my wordlistjump to other resultssomething you say by mistake but which is believed to show your true thoughts This expression is named after Sigmund Freud and his theories of unconscious thought.See Freudian slip in the Oxford Advanced American DictionaryCheck pronunciation: Freudian slip oxfordlearnersdictionaries.com