Definition of undeniable :
1. Not deniable; incapable of denial; palpably true; indisputable; obvious; as, undeniable evidence.
2. Unobjectionable; unquestionably excellent; as, a person of undeniable connections.
necessary, undisputable, accomplished, inevitable, inarguable, unarguable, ineluctable, needful, objective, requisite, realistic, infallible, unavoidable, needed, essential, authentic, unchallengeable, factual, firm, hard, definitely, required, true, indispensable, unanswerable, unassailable
absolute (part of speech: adjective)
certain (part of speech: adjective)
doubtless, irrefutable, set, confident, indisputable, veritable, trusting, convinced, clear, patent, unquestionable, decided, incontestable, assured, decisive, undoubted, steadfast, unmistakable, irrefragable, incontrovertible
categorical (part of speech: adjective)
- Could there be anything worse from the point of view of his undeniable cleverness? - "An Outcast of the Islands", Joseph Conrad.
- The opportunity was undeniable. - "The Hole in the Wall", Arthur Morrison.
- An undeniable character is a character that cannot be denied, whether bad or good. - "How to Speak and Write Correctly", Joseph Devlin.