adjective
- not open to question; beyond doubt or dispute; indisputable; undeniable; certain: an unquestionable fact.
- above criticism; unexceptionable: a man of unquestionable principles.
adverb
- indisputably; definitelyan unquestionably great club
- (sentence modifier) without a doubt; certainlyunquestionably there were costs incurred
adjective
- indubitable or indisputable
- not admitting of exception or qualificationan unquestionable decision
adj.c.1600, from un- (1) “not” + questionable. Related: Unquestionably.