› not correct or true: "Three plus three is seven. True or false?" "False." Note: said about information or an idea falsely /ˈfɔls·li/ adv [not gradable] › She was falsely accused of shoplifting. falsity /ˈfɔl·sɪ·t̬i/ n [U] (also falseness /ˈfɔl·snəs/) › fml We’re trying to determine the truth or falsity of your previous statement.