dubiosity
The state or characteristic of being dubious; a dubious assertion.
countable, rare, uncountable
[M]en often ſwallow falſities for truths, dubioſities for certainties, feſibilities for poſſibilities, and things impoſſible as poſſibilities themſelves.
Where it comes from
From dubious, after such pairs as curious: curiosity; adaptation of a Latin-type *dubiōsitās; compare Italian dubbiosità.
Adapted from the Wiktionary entry dubiosity (CC BY-SA 4.0).