adjective
absolutely certain
Synonyms: beyond doubt, cinched, clear-cut, clinched, confirmed, decided, definite, dependable, ensured, fixed, guaranteed, indubitable, insured, in the bag, irrefutable, made certain, nailed down, on ice, pronounced, racked, sealed, secure, set, settled, sewed up, sure, surefire, undoubted, unquestionable
Antonyms: doubted, doubtful, feared, uncertain
adjective
confident
Synonyms: assertive, audacious, bold, brazen, certain, cocksure, collected, complacent, composed, confident, cool, gung ho, gutsy, high, imperturbable, overconfident, poised, positive, puffed up, pumped up, pushy, rosy, sanguine, secure, self-assured, self-confident, self-possessed, sure, unflappable, unhesitating, upbeat
Antonyms: confused, dismayed, distrustful, doubtful, doubting, fearful, hesitant, nervous