Antonyms of adj portentous

3 senses of portentous

Sense 1
portentous, prodigious -- (of momentous or ominous significance; "such a portentous...monster raised all my curiosity"- Herman Melville; "a prodigious vision")

INDIRECT (VIA significant) -> insignificant, unimportant -- (devoid of importance, meaning, or force)

Sense 2
fateful, foreboding (prenominal), portentous -- (ominously prophetic)

INDIRECT (VIA prophetic) -> unprophetic -- (not prophetic; not foreseeing correctly)

Sense 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)

INDIRECT (VIA pretentious) -> unpretentious -- (lacking pretension or affectation; "an unpretentious country church"; "her quiet unpretentious demeanor")

Similarity of adj portentous

3 senses of portentous

Sense 1
portentous, prodigious -- (of momentous or ominous significance; "such a portentous...monster raised all my curiosity"- Herman Melville; "a prodigious vision")
       => significant (vs. insignificant), important -- (important in effect or meaning; "a significant change in tax laws"; "a significant change in the Constitution"; "a significant contribution"; "significant details"; "statistically significant")

Sense 2
fateful, foreboding (prenominal), portentous -- (ominously prophetic)
       => prophetic (vs. unprophetic), prophetical -- (foretelling events as if by supernatural intervention; "prophetic writings"; "prophetic powers"; "words that proved prophetic")

Sense 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)
       => pretentious (vs. unpretentious) -- (making claim to or creating an appearance of (often undeserved) importance or distinction; "a pretentious country house"; "a pretentious fraud"; "a pretentious scholarly edition")