SERIOUS Synonyms: 183 Similar and Opposite Words

Q: How is the word 'serious' different from other adjectives like it?

Some common synonyms of serious are earnest , grave , sedate , sober , solemn , and staid . While all these words mean "not light or frivolous," serious implies a concern for what really matters. // a serious play about social injustice

Q: In what contexts can 'earnest' take the place of 'serious'?

Although the words earnest and serious have much in common, earnest suggests sincerity or often zealousness of purpose. // an earnest reformer

Q: When would 'grave' be a good substitute for 'serious'?

While in some cases nearly identical to serious , grave implies both seriousness and dignity in expression or attitude. // read the proclamation in a grave voice

Q: When is it sensible to use 'sedate' instead of 'serious'?

While the synonyms sedate and serious are close in meaning, sedate implies a composed and decorous seriousness. // remained sedate amid the commotion

Q: Where would 'sober' be a reasonable alternative to 'serious'?

The words sober and serious are synonyms, but do differ in nuance. Specifically, sober stresses seriousness of purpose and absence of levity or frivolity. // a sober look at the state of our schools

Q: When might 'solemn' be a better fit than 'serious'?

The synonyms solemn and serious are sometimes interchangeable, but solemn suggests an impressive gravity utterly free from levity. // a sad and solemn occasion

Q: When is 'staid' a more appropriate choice than 'serious'?

In some situations, the words staid and serious are roughly equivalent. However, staid suggests a settled, accustomed sedateness and prim self-restraint. // a quiet and staid community

serious

adjective

ˈsir-ē-əs

Definition of serious

as in solemn

not joking or playful in mood or manner I'm serious when I say that no one should be walking in that neighborhood at night

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in important

having a matter of importance as its topic a very serious film that dealt with the aftermath of the Gulf War

Synonyms & Similar Words

Antonyms & Near Antonyms

as in dangerous

involving potential loss or injury a serious accident

Synonyms & Similar Words

Antonyms & Near Antonyms

Synonym Chooser

How is the word serious different from other adjectives like it?

Some common synonyms of serious are earnest, grave, sedate, sober, solemn, and staid. While all these words mean "not light or frivolous," serious implies a concern for what really matters.

a serious play about social injustice

In what contexts can earnest take the place of serious?

Although the words earnest and serious have much in common, earnest suggests sincerity or often zealousness of purpose.

an earnest reformer

When would grave be a good substitute for serious?

While in some cases nearly identical to serious, grave implies both seriousness and dignity in expression or attitude.

read the proclamation in a grave voice

When is it sensible to use sedate instead of serious?

While the synonyms sedate and serious are close in meaning, sedate implies a composed and decorous seriousness.

remained sedate amid the commotion

Where would sober be a reasonable alternative to serious?

The words sober and serious are synonyms, but do differ in nuance. Specifically, sober stresses seriousness of purpose and absence of levity or frivolity.

a sober look at the state of our schools

When might solemn be a better fit than serious?

The synonyms solemn and serious are sometimes interchangeable, but solemn suggests an impressive gravity utterly free from levity.

a sad and solemn occasion

When is staid a more appropriate choice than serious?

In some situations, the words staid and serious are roughly equivalent. However, staid suggests a settled, accustomed sedateness and prim self-restraint.

a quiet and staid community

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of serious At least three of our victims have sustained serious injuries and one of those is in critical condition. — ABC News, 25 Oct. 2026 The answer is mostly yes, especially now that the highest trim level brings some serious Harman Kardon punch. — New Atlas, 24 Oct. 2026 The convergence of young people’s anger over education and employment, fears of authoritarianism, and concern for the sanctity of the vote poses a serious challenge to the Modi government. — Asim Ali, Time, 24 Oct. 2026 Who should avoid mouth tape Specialists say the bigger worry is that mouth tape can mask something more serious happening in your airway. — Samantha Agate, Sacbee.com, 24 Oct. 2026 See All Example Sentences for serious

Recent Examples of Synonyms for serious

Adjective

The spirituality throughout is imbued with a solemn reverence more Catholic than Baptist.

— Kiana Mickles, Pitchfork, 13 Oct. 2026
This production, solemn about our obligations to one another but committed to providing a good night out at the theater, is neither.

— Daniel D'Addario, Variety, 2 Oct. 2026

Definition of solemn

Adjective

Helium plays an important role in wind, solar and nuclear energy production, space exploration, medical imaging and research.

— Arkansas Online, Arkansas Online, 24 Oct. 2026
Education and giving back are important values to the family as the project represents for them a broader impact within the natural diamond industry.

— Fairchild Studio, Footwear News, 24 Oct. 2026

Definition of important

Adjective

In November 2021, crew members took shelter inside their spacecraft after a Russian anti-satellite weapons test created a dangerous cloud of debris.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026
In 2015, Chicago’s public health department identified three cases of invasive meningococcal disease, a highly dangerous pathogen that can kill within hours.

— Julie Morita, Time, 25 Oct. 2026

Definition of dangerous

Adjective

The crisis capped a week of severe weather in which rain swamped dozens of homes in Utah and tornadoes blew off roofs, knocked trees onto houses and downed power lines in Arizona.

— MEAD GRUVER, Arkansas Online, 24 Oct. 2026
Daniel Swain, a climate scientist with the University of California Agriculture and Natural Resources, says the severe thunderstorms are fueled by the large amount of moisture in the air.

— Ava Berger, NPR, 24 Oct. 2026

Definition of severe

Adjective

If enough collisions occur, certain orbital regions could become extremely hazardous for future missions.

— Kurt Knutsson, FOXNews.com, 25 Oct. 2026
Today, the vast majority of this hazardous waste remains locked in temporary storage facilities across the globe.

— Mrigakshi Dixit, Interesting Engineering, 23 Oct. 2026

Definition of hazardous

Adjective

Contemplation of this tax — which produced $384 million in the last fiscal year — has consumed endless hours of work from some of the county’s most respected leaders, and drawn earnest public testimony from dozens of people.

— Orlando Sentinel Editorial Board, The Orlando Sentinel, 18 Oct. 2026
The video plays hopscotch with tone—at once horrific, ridiculous, and bathetically earnest.

— Eugenie Brinkema, ARTnews.com, 17 Oct. 2026

Definition of earnest

Browse Nearby Words

series

serious

seriously

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Style

“Serious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/serious. Accessed 28 Oct. 2026.

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Synonyms of serious

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