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 Over the past three years, officials say Bristol has seen 90 serious injuries and 20 fatalities due to preventable traffic deaths. — Stephen Underwood, Hartford Courant, 18 Oct. 2026 The papers are said to have contained highly sensitive information, some likely supplied by Germany’s intelligence partners – so the affair could have serious international ramifications at a time when Europe is facing grave security threats. — The Week Uk, TheWeek, 17 Oct. 2026 Qualifying risks must involve more than $1 billion in damages or the deaths or serious injuries of over 50 people. — Aamir Khollam, Interesting Engineering, 17 Oct. 2026 While the Broncos haven’t returned to the tournament since then, this year’s squad blends continuity with exciting new faces and stands a serious chance of bringing Boise State back to the NCAA Tournament. — Shaun Goodwin, Idaho Statesman, 17 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

Understanding the answer is often more important than the opportunity itself.

— Aneri Jambusaria, Fortune, 18 Oct. 2026
Ties between Ukraine and its most important backer the United States have also been strained by the apparent withdrawal of US intelligence sharing, and restrictions to the Starlink satellite internet service.

— Helen Regan, CNN Money, 17 Oct. 2026

Definition of important

Adjective

Swimmers should remain out of the water due to dangerous surf conditions.

— NC Weather Bot, Charlotte Observer, 18 Oct. 2026
Fresh to strong winds will produce dangerous boating conditions, high surf, life-threatening rip currents, and moderate beach erosion through at least the first half of the coming week, forecasters said.

— Felix Rodriguez, The Orlando Sentinel, 18 Oct. 2026

Definition of dangerous

Adjective

Trump's continuing criticism of Ukrainian President Volodymyr Zelenskyy and praise of Putin only give Putin further confidence the United States is not serious about imposing more severe sanctions.

— Arkansas Online, Arkansas Online, 17 Oct. 2026
That role demands reliable equipment capable of transmitting strategic instructions during severe national security crises.

— Aamir Khollam, Interesting Engineering, 17 Oct. 2026

Definition of severe

Adjective

At the end of September, leaders of several of the biggest AI companies went to the White House and signed an accord committing to internal risk controls, independent audits and board-level oversight of safety.

— Giorgos Tsetis, Fortune, 17 Oct. 2026
Go rebound the basketball, go protect the rim, be a big big for us.

— Anthony Chiang, Miami Herald, 17 Oct. 2026

Definition of big

Adjective

Ultimately, the greatest impacts will be determined by the storm's track, but periods of heavy rain and wind, along coastal flooding, beach erosion, and hazardous surf are a concern, especially for the Carolinas and mid-Atlantic.

— ABC News, ABC News, 17 Oct. 2026
Preliminary tests indicate the substance is not hazardous; the letters prompted evacuations and police responses, with no injuries reported in the California incidents described.

— Los Angeles Times, Los Angeles Times, 17 Oct. 2026

Definition of hazardous

Adjective

Of the young adults that comprise Ellora’s defense force, earnest airbender Jae (Major Curda) and himbo waterbender Daemin (Darren Barnet) make for a particularly amusing pairing.

— Angie Han, HollywoodReporter, 9 Oct. 2026
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

Definition of earnest

Browse Nearby Words

series

serious

seriously

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“Serious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/serious. Accessed 20 Oct. 2026.

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