1. (

• portentous ,
• prodigious

) of momentous or ominous significance; "such a portentous...monster raised all my curiosity"- Herman Melville; "a prodigious vision" ;

2. (

• fateful ,
• foreboding ,
• portentous

) ominously prophetic ;

3. (

• grandiloquent ,
• overblown ,
• pompous ,
• pontifical ,
• portentous

) puffed up with vanity; "a grandiloquent and boastful manner"; "overblown oratory"; "a pompous speech"; "pseudo-scientific gobbledygook and pontifical hooey"- Newsweek ;