adjective
certain, definite
Synonyms: absolute, assured, categorical, cinched, clear, clear-cut, clinched, destined, determined, distinct, emphatic, explicit, express, fated, for sure, indisputable, in the bag, nailed, on ice, positive, prearranged, predetermined, pronounced, resolved, runaway, settled, sure, unalterable, unambiguous, undeniable, undisputed, unequivocal, unmistakable, unquestionable
Antonyms: indefinite, uncertain, undecided
adjective
determined, strong-willed
Synonyms: assertive, bent, certain, cocksure, decisive, deliberate, earnest, emphatic, established, firm, fixed, inflexible, intent, iron-jawed, mulish, positive, purposeful, resolute, resolved, serious, set, settled, strong-minded, sure, unbending, unfaltering, unhesitating, unwavering, unyielding
Antonyms: deferential, delaying, hesitant, postponing, procrastinating, undecided