adjective
1.
Synonyms: authentic 2, bona fide, genuine, indubitable, real, sure-enough, true, undoubted, veritable, very
Antonyms: doubtable, questionable
2.
Synonyms: positive 3, certain, incontestable, incontrovertible, indisputable, indubitable, uncontestable, undeniable, undisputable, unequivocal
Related Word: dependable, reliable; established, well-founded, well-grounded
Antonyms: doubtable, questionable
3.
Synonyms: downright 2, flat, indubitable, up-and-down