Synonyms for sure

assured, certain, confident, convinced, definite, dependable, destined, emphatic, foolproof, guaranteed, indisputable, infallible, irrefragable, irrefutable, known, positive, reliable, satisfied, secure, self-assured, steadfast, steady, sure-fire, trusted, trusty, unarguable, undebatable, undisputable, undoubted, unequivocal, unerring, unfailing, unquestionable, yeah, yes