Meaning of the word portentous in English

What does portentous mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

portentous

US /pɔːrˈten.t̬əs/
UK /pɔːˈten.təs/

Adjective

too serious and trying to be very important:

Example:
The problem with the book is that it sometimes descends into portentous philosophizing.