unquestioned vs unchallenged

unquestioned and unchallenged both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unquestioned	No	Yes	No	No
unchallenged	No	Yes	No	No

As adjectives, unquestioned and unchallenged are synonyms defined as:

unquestioned and unchallenged: generally agreed upon; not subject to dispute

Other synonyms of unquestioned include undisputed.

unquestioned (adjective)	unchallenged (adjective)
generally agreed upon; not subject to dispute	generally agreed upon; not subject to dispute