Antonym of doubtful

Antonyms of adj doubtful

3 senses of doubtful

Sense 1:

doubtful, dubious, dubitable, in question(predicate)

INDIRECT (VIA questionable) -> unquestionable

Sense 2:

doubtful, dubious

INDIRECT (VIA uncertain, unsure) -> certain, sure
INDIRECT (VIA uncertain, unsure) -> certain, sure

Sense 3:

doubtful, tentative

INDIRECT (VIA unsettled) -> settled