nubilous

[ noo-buh-luh s, nyoo- ]
/ ˈnu bə ləs, ˈnyu- /

adjective

cloudy or foggy.
obscure or vague; indefinite.

Origin of nubilous

1525–35; < Latin nūbilus, equivalent to nūb(ēs) cloud + -ilus adj. suffix. See -ous