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 Still, there’s some serious potential here for an entertaining redemption (or final damnation) arc for Joe, and the other cats of Team Lioness should a fourth season materialize. — Andy Andersen, Vulture, 20 Sep. 2026 The person shot is in serious but stable condition, Austin Mayor Kirk Watson said in a press conference. — Sergio Martínez-Beltrán, NPR, 20 Sep. 2026 And now both — still just 26 and 25, respectively — are among the newest members of Hollywood’s A-list, and very serious contenders for Oscar nominations. — Scott Feinberg, HollywoodReporter, 20 Sep. 2026 Charging a 621-kWh battery takes serious power Eventually, even this giant battery has to plug in. — Kurt Knutsson, FOXNews.com, 20 Sep. 2026 See All Example Sentences for serious

Recent Examples of Synonyms for serious

Adjective

Yom Kippur, which is coming on Monday, is the most solemn time on the Jewish calendar, is a day of introspection, self-examination, self-evaluation, and self-reflection.

— Marc Schneier, New York Daily News, 18 Sep. 2026
The night, centered on the foundation’s ongoing push to fund a cure and support those stigmatized by their HIV status, didn’t end on that solemn note.

— Rebecca Ford, Vanity Fair, 18 Sep. 2026

Definition of solemn

Adjective

Yet he was accused of failing to do his work as recently as November, detained in a neighboring village over rainfall that disrupted an important ceremony.

— Arkansas Online, Arkansas Online, 20 Sep. 2026
Maybe the most important thing Jon Sumrall did Saturday night wasn’t beating Auburn.

— Mike Bianchi, The Orlando Sentinel, 20 Sep. 2026

Definition of important

Adjective

Never mix vinegar with bleach, as the combination can create dangerous chlorine gas.

— The Spruce, The Spruce, 20 Sep. 2026
As the news of the helicopter crash spread, media crews from the bus accident scene began rushing to the helicopter site and were told by law enforcement to evacuate because the situation was too dangerous, NBC4 footage showed.

— Dalia Faheid, CNN Money, 20 Sep. 2026

Definition of dangerous

Adjective

This appointment arrives as Nike navigates deep operational restructuring and severe market headwinds.

— , CNBC, 18 Sep. 2026
Six decades earlier, on the same grounds, a young Muhammad Ali absorbed a famous left hook from Henry Cooper late in the fourth round, then finished the fight in the fifth when the referee stopped it because of a severe cut over Cooper’s eye.

— Gary Bedore, Kansas City Star, 18 Sep. 2026

Definition of severe

Adjective

These include dynamic proton radiography, materials science, neutron scattering, and nuclear physics, all operating at a facility authorized to use hazardous materials and handle classified data.

— Rupendra Brahambhatt, Interesting Engineering, 19 Sep. 2026
In regards to what is happening on the streets of NYC — Kaporos — thousands of young Cornish chickens are kept in the streets in crates, in hazardous and dangerous conditions.

— Voice of the People, New York Daily News, 19 Sep. 2026

Definition of hazardous

Adjective

Nora’s time in the office, and the relationships that blossom — and one that withers — over the course of that formative span give shape to this earnest, appealing movie about idealism lost but innocence preserved.

— Natalia Winkelman, Variety, 20 Sep. 2026
Presented on a bold black-and-white print, Ghost Song is an earnest and spiritually rich film that Akin says was born out of a period of crisis in his career.

— Zac Ntim, Deadline, 18 Sep. 2026

Definition of earnest

Adjective

That led to the Sox leading the majors in relief innings this season and being on a pace to finish with 764 innings, which would rank third in major-league history.

— Paul Sullivan, Chicago Tribune, 19 Sep. 2026
In a surprise move, and major upset for competitor Nike, On has inked a deal with Real Madrid forward Kylian Mbappé to be the face of its new football category.

— Stephen Garner, Footwear News, 18 Sep. 2026

Definition of major

Browse Nearby Words

series

serious

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Style

“Serious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/serious. Accessed 26 Sep. 2026.

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