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Showing results for serious. Search instead for seriou.
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 marked the symbolic beginning of her ministry as archbishop, a role to which she was appointed after her predecessor Justin Welby resigned in 2024 after criticism of his handling of a serious abuse case.

From BBC • Apr. 4, 2026

Any serious solar geoengineering project is probably decades away, but perhaps that’s a good reason to accelerate development now.

From Salon • Apr. 4, 2026

“If you want to be serious, you don’t go around saying the opposite of what you said the day before,” Macron said.

From The Wall Street Journal • Apr. 3, 2026

Comedian Eugene Mirman, the voice of Gene on ‘Bob’s Burgers,’ was pulled from a fiery car crash and taken to a hospital with serious injuries.

From Los Angeles Times • Apr. 3, 2026

I nod, understanding by the earnest look in his eye that he’s very serious, and that me following through on my plans to apply to Sunridge is, for some reason, important to him.

From "Red Flags and Butterflies" by Sheryl Azzam

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