as in astonishing
causing wonder or astonishment in 1969 people regarded the first landing on the moon as a truly portentous event

Synonyms & Similar Words

Antonyms & Near Antonyms

Synonym Chooser

How does the adjective portentous differ from other similar words?

The words fateful and ominous are common synonyms of portentous. While all three words mean "having a menacing or threatening aspect," portentous suggests being frighteningly big or impressive but now seldom definitely connotes forewarning of calamity.

an eerie and portentous stillness

When is it sensible to use fateful instead of portentous?

In some situations, the words fateful and portentous are roughly equivalent. However, fateful suggests being of momentous or decisive importance.

the fateful conference that led to war

When can ominous be used instead of portentous?

The words ominous and portentous are synonyms, but do differ in nuance. Specifically, ominous implies having a menacing, alarming character foreshadowing evil or disaster.

ominous rumblings from the volcano


Thesaurus Entries Near portentous

Cite this Entry

“Portentous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/portentous. Accessed 22 Mar. 2023.

More from Merriam-Webster on portentous

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