[1] : The Collaborative International Dictionary of English v.0.48

unchallengeable \unchallengeable\
   see challengeable.
see also:
challengeable 

[2] : WordNet (r) 2.0

unchallengeable
     adj : not open to challenge; "unchallengeable facts"; "a position
           of unchallengeable supremacy"

[3] : Moby Thesaurus II by Grady Ward, 1.0

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

Unchallengeable >> U Words
Unchallengeable, definition of term: Unchallengeable
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