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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.

This age group of drivers account for 24% of fatal or serious collisions despite holding just 8% of licences, she added.

From BBC • Apr. 5, 2026

Because saliva plays a key role in controlling bacteria and maintaining oral health, its loss can lead to serious dental problems.

From Science Daily • Apr. 5, 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

It remains Galsworthy’s most famous individual novel and established him as a serious writer and a progressive public voice.

From The Wall Street Journal • Apr. 3, 2026

All of this was in minutes that seemed like hours and I realized that I was in serious trouble.

From "Woodsong" by Gary Paulsen

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