unchallengeable adj 1: not open to challenge; "unchallengeable facts"; "a position of unchallengeable supremacy"
Unchallengeable \Unchallengeable\ See {challengeable}.
22 Moby Thesaurus words for "unchallengeable": deep-seated, esoteric, immanent, implanted, implicit, inalienable, indwelling, infixed, ingrained, inherent, inner, internal, intrinsic, inward, inwrought, irreducible, private, resident, secret, subjective, unalienable, unquestionable