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 In a news release Friday, Leavenworth County Attorney Todd Thompson said bringing a weapon to school and knowingly making a false report about one can have serious consequences under state law. — Nathan Pilling, Kansas City Star, 4 Oct. 2026 The Sun in your sign opposes Saturn in your 7th House, putting relationships, commitments, and compromise under a more serious lens. — Tarot.com, New York Daily News, 4 Oct. 2026 What changes are needed to ensure that serious concerns raised at individual campuses receive meaningful review and action? — Dr. Matthew Warshauer, Hartford Courant, 4 Oct. 2026 The unusual 3-5-5 defensive scheme Hauck installed was plagued by serious communication issues between players and coaches during the ex-Montana coach’s four-game tenure. — Steve Stein, Chicago Tribune, 4 Oct. 2026 See All Example Sentences for serious

Recent Examples of Synonyms for serious

Adjective

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
Zack Wheeler pitched a gem against Tampa Bay on Sunday and untangled a few thousand knots inside the stomachs of Phillies fans, and even from those inside a mostly solemn clubhouse.

— CBS News, CBS News, 28 Sep. 2026

Definition of solemn

Adjective

While a push east for Marib would get the Houthis the most resources, a southern push appears to be more strategically important for the time being.

— Brady Knox, The Washington Examiner, 4 Oct. 2026
For decades, the European Union has led the world in implementing policies designed to cut emissions, creating the world’s most important price on carbon and crafting the rules of the road for a wide range of regulatory efforts.

— Justin Worland, Time, 3 Oct. 2026

Definition of important

Adjective

Meanwhile, the financial clout of the industry has grown considerably, resulting in a new, more dangerous problem.

— Kent Sepkowitz, STAT, 5 Oct. 2026
Attempting to de-escalate the scare, Rospotrebnadzor declared the regional sanitary situation stable after secondary testing showed no traces of dangerous pathogens linked to Shipilova’s research.

— Mrigakshi Dixit, Interesting Engineering, 5 Oct. 2026

Definition of dangerous

Adjective

Regional forecasts are often concerned with extreme events, such as heavy rainfall, squall lines, severe thunderstorms or hurricanes.

— Chanh Kieu, Washington Post, 2 Oct. 2026
Measles vaccination rates are low, families are large, and people may not seek care unless the illness becomes severe.

— STAT, STAT, 2 Oct. 2026

Definition of severe

Adjective

However, Ukraine has this year made some progress against Russia's bigger army, according to the Institute for the Study of War.

— HANNA ARHIROVA, Arkansas Online, 3 Oct. 2026
Orlando Bloom’s first big automotive splurge was a classic Porsche—a black 911S from 1973.

— Brett Berk, Robb Report, 2 Oct. 2026

Definition of big

Adjective

Ensure heat is working so tenants don’t need space heaters, which can be particularly hazardous in buildings with older electrical systems.

— Lillian Bonsignore, New York Daily News, 4 Oct. 2026
The action comes as Livingston locals raised concerns about the film’s impact on local business — and notably the city’s sole food bank — as well as improper notification about hazardous stunts.

— Payton Turkeltaub, Variety, 4 Oct. 2026

Definition of hazardous

Adjective

A certain ingenuousness, an earnest impatience with the world’s many injustices, is a hallmark of Barbara Kingsolver’s novels.

— Sam Worley, Vulture, 5 Oct. 2026
Such requests typically don’t start in earnest until closer to the end of the fourth quarter, which is why most TV networks don’t like to declare sell-out until just days before the Super Bowl starts.

— Brian Steinberg, Variety, 5 Oct. 2026

Definition of earnest

Adjective

Wildfires encroached on major European cities, a once unthinkable threat.

— Justin Worland, Time, 3 Oct. 2026
These five rising, behind-the-scenes maestros have worked on major hits for such likely 2027 contenders as Noah Kahan, Ariana Grande and Rosalía — and could be first-time nominees in the category.

— Andrew Unterberger, Billboard, 2 Oct. 2026

Definition of major

Browse Nearby Words

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Style

“Serious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/serious. Accessed 9 Oct. 2026.

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Synonyms of serious

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