in·tol·er·ant / inˈtälərənt/ • adj. not tolerant of others' views, beliefs, or behavior that differ from one's own: he was intolerant of ignorance. ∎ unable to be given (a medicine or other treatment) or to eat (a food) without adverse effects: intolerant of aspirin | these patients were lactose intolerant. ∎ (of a plant or animal) unable to survive exposure to (physical influence). DERIVATIVES: in·tol·er·ance n. in·tol·er·ant·ly adv.