U0034200 (ŭn-chăl′ən-jə-bəl)adj. Not open to challenge: unchallengeable facts.un·chal′lenge·a·bly adv.Thesaurus
Adj.
1.
unchallengeable - not open to challenge; "unchallengeable facts"; "a position of unchallengeable supremacy"noncontroversial, uncontroversial - not likely to arouse controversy
unchallengeable - not open to challenge; "unchallengeable facts"; "a position of unchallengeable supremacy"