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Showing results for serious. Search instead for erioph.
Definitions

serious

[seer-ee-uhs] / ˈsɪər i əs /
ADJECTIVE
somber, humorless
Synonyms
STRONGEST
deliberate genuine honest severe sincere thoughtful
STRONG
sober
WEAK
austere bound bound and determined businesslike cold sober contemplative deadpan determined downbeat earnest funereal go for broke grave grim intent long-faced meditative no-nonsense pensive pokerfaced reflective resolute resolved sedate set solemn staid steady stern unhumorous unsmiling weighty
Antonyms
STRONGEST
deceptive dishonest false insincere misleading untrustworthy
WEAK
flippant funny happy light minor trivial unimportant unserious
ADJECTIVE
crucial, weighty
Synonyms
STRONGEST
dangerous deep difficult far-reaching grievous important major meaningful severe significant tough urgent
WEAK
arduous fateful fell formidable grave grim hard heavy laborious meaning business menacing momentous no joke no laughing matter of consequence operose out for blood playing hard ball pressing smoking sobering strenuous strictly business threatening ugly unamusing unhumorous worrying
Antonyms
STRONGEST
calm easy facile friendly insignificant little meaningless minor small trivial unimportant worthless
WEAK
flippant funny happy light unserious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It also poses a serious risk during pregnancy.

From Science Daily • Apr. 6, 2026

"I'm very worried, because my grandfather actually had a very serious stroke. I hope I don't have a full stroke before I am seen," he told BBC News.

From BBC • Apr. 6, 2026

But at the same time, she said that if the Iran conflict were to drag on for longer than a few months, it could have serious repercussions for markets and the U.S. economy.

From MarketWatch • Apr. 6, 2026

The Cuban leader, who confirmed in March that US and Cuban officials had held talks, reiterated his government's willingness to "engage in serious and responsible bilateral dialogue, and finding solutions to existing differences."

From Barron's • Apr. 6, 2026

I don’t think I’ve seen him serious ever.

From "Clairboyance" by Kristiana Kahakauwila

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.