portentous
por-ten-tous
adjective
Trying to seem very serious and important, often in an exaggerated or pompous way.
"His portentous speech bored everyone."
adjective
Suggesting something important or bad is about to happen; ominous or foreboding.
"The dark clouds had a portentous quality."
Thesaurus
Synonyms: foreboding, prophetic, fateful, prophetical, significant, prodigious, important, overblown, pretentious, grandiloquent, pontifical, pompous