unchallengeable From WikiWord, the free dictionary English Contents DefinitionsRelated wordsReferences DefinitionsadjectiveNot open to challenge; indisputable Related wordsSynonymsinarguableindisputableunarguableunquestionableundeniableundisputableunmistakableundisputedincontrovertibleinescapableincontestableundoubteduncontestedunquestionedunchallengeduncontrovertableinoppugnableuncontestable References Wiktionary — unchallengeable Wikipedia — unchallengeable