The quality or state of being doubtful, questionable, or uncertain; the characteristic of arousing doubt or suspicion.
From 'dubious' plus the common English suffix '-ness,' which creates abstract nouns from adjectives. 'Dubious' itself comes from Latin 'dubius' meaning wavering or uncertain.
English speakers prefer 'dubiousness' over the Latin-derived 'dubiosity'—it's more natural-sounding, which shows how English constantly simplifies borrowed words into everyday forms.
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