mistrust vs dubiousness

mistrust and dubiousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
mistrust	Yes	No	Yes	No
dubiousness	Yes	No	No	No

As nouns, dubiousness is a hypernym of mistrust; that is, dubiousness is a word with a broader meaning than mistrust:

Other hypernyms of mistrust include doubt, doubtfulness, dubiety, incertitude, uncertainty.

mistrust (noun)	dubiousness (noun)
the trait of not trusting others	uncertainty about the truth or factuality or existence of something
doubt about someone's honesty	the state of being unsure of something

mistrust (verb)	dubiousness (verb)
regard as untrustworthy; regard with suspicion; have no faith or confidence in