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 There are serious concerns about whether there have been violations of the tax system's protections against political interference, and those concerns warrant investigation. — Tax Notes Staff, Forbes.com, 30 June 2026 Beijing has and been accused of serious human violations, including large-scale arbitrary detention of Uyghur and other Muslim minorities, in Xinjiang. — Simone McCarthy, CNN Money, 1 July 2026 Prosecutors said Anthony Edmond and Rafael Enriquez face the most serious charges, including conspiracy involving firearms trafficking, machineguns and drug trafficking. — Michael Sinkewicz, FOXNews.com, 1 July 2026 Then there's Colorado's 1st Congressional District, where a 29-year-old lawyer is mounting a serious challenge against 15-term DeGette, proving to be the most formidable primary opponent the incumbent has faced since she was first elected in 1996. — Kaia Hubbard, CBS News, 30 June 2026 See All Example Sentences for serious

Recent Examples of Synonyms for serious

Adjective

Ureña, a 22-year-old right-hander who has emerged as another potential ace, speaks of Soriano with a giddy amusement mixed with a solemn respect for how the starter has survived in the big leagues.

— Liana Handler, Los Angeles Times, 30 June 2026
Dozens of firefighters lined the street in a solemn salute to their fallen colleagues.

— Chelsea Bailey, CNN Money, 29 June 2026

Definition of solemn

Adjective

One interesting trend is that this tournament will feature some very good tight ends, a position that has become increasingly important in college football and the NFL but not so much in high school football in the era of spread offenses.

— Eric Sondheimer, Los Angeles Times, 5 July 2026
As technology becomes more sophisticated and the number of living survivors continues to decline, preserving authentic testimony becomes even more important.

— Eva Weiss, Sun Sentinel, 5 July 2026

Definition of important

Adjective

Teri handled higher-value finds and saw that potentially dangerous items – like firearms and knives – got to the local sheriff’s office.

— Alisha Ebrahimji, CNN Money, 6 July 2026
Looking back through the sequence, Brazil have good numbers back and there is little need for anyone to overcommit — but a lazy tackle from behind leads to a free kick in a dangerous area.

— Mark Carey, New York Times, 6 July 2026

Definition of dangerous

Adjective

Ruffian, racing on the lead, sustains a severe leg injury and is pulled up by jockey Jacinto Vasquez.

— Assistant Sports Editor, Los Angeles Times, 6 July 2026
The incident occurred on Sunday, July 5, near the front entrance of the Austell theme park after severe weather hit the area, according to Fox 5 Atlanta.

— Becca Longmire, PEOPLE, 6 July 2026

Definition of severe

Adjective

Meta, Oracle, Microsoft and other big tech companies have laid off tens of thousands of employees, while simultaneously investing billions in AI data centers.

— Los Angeles Times, Los Angeles Times, 4 July 2026
Also in attendance to celebrate the couple on their big day was Dunham's ex and Swift's longtime collaborator, Jack Antonoff, who was seen leaving for the event with his sister, Rachel Antonoff.

— Yamillah Hurtado, PEOPLE, 4 July 2026

Definition of big

Adjective

What Kenzie describes — the discovery that belonging generates effort, that trust compounds, that earnest investment in an institution can be returned — is precisely what defensive foreclosure costs.

— Nick Lichtenberg, Fortune, 6 July 2026
The earnest post follows a flurry of recent activity on Biden's social media.

— Madison E. Goldberg, PEOPLE, 1 July 2026

Definition of earnest

Adjective

Maybe Bill Plaschke would be aware of that, and give due credit, if his hometown major newspaper bothered to have a dedicated correspondent covering one of the city’s NBA teams.

— Los Angeles Times, Los Angeles Times, 4 July 2026
Some of these storms could be severe and deliver damaging wind gusts, but any thunderstorm will contain lightning — a major danger for any outdoor activities, especially for anyone trying to escape the heat in or on the water.

— Mary Gilbert, CNN Money, 4 July 2026

Definition of major

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“Serious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/serious. Accessed 7 Jul. 2026.

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