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 Prosecutors opted to retry Read, and she was acquitted of the most serious charges, second-degree murder and leaving the scene of a collision resulting in death, in June 2025. — Melina Khan, USA Today, 1 Sep. 2026 Making cookies from plastic bottles Plastic pollution is a serious environmental concern, and microbes are helping scientists mitigate the issue in a variety of ways. — ArsTechnica, 1 Sep. 2026 Some of them sounded serious, like How to Organize Yourself—very practical. — Caitlín Doherty, Artforum, 1 Sep. 2026 The woman did not suffer any serious injuries, according to police. — Brenton Blanchet, PEOPLE, 1 Sep. 2026 See All Example Sentences for serious

Recent Examples of Synonyms for serious

Adjective

The slow chimes of Big Ben sounded, and then the newsreader’s solemn voice with the headlines.

— Helen Simpson, New Yorker, 30 Aug. 2026
In addition, the new king will receive a solemn ecclesiastical blessing in Nidaros Cathedral in Trondheim.

— Stefania Conrieri, Vanity Fair, 28 Aug. 2026

Definition of solemn

Adjective

That has changed quietly, with robots now performing important roles in operating rooms, hospital wards, rehabilitation centers, and corridors around the world.

— Atharva Gosavi, Interesting Engineering, 30 Aug. 2026
Reseeding is particularly important in high-traffic areas or patches of the lawn where grubs, heat, or disease have left the turf thin.

— Mary Marlowe Leverette, The Spruce, 29 Aug. 2026

Definition of important

Adjective

The death toll from severe flooding along the Nepal-China border on Wednesday has climbed to 762 in Nepal, local police said, as rescue crews scour devastated neighborhoods for survivors.

— Bhadra Sharma, CNN Money, 30 Aug. 2026
The bleeding was severe, her blood pressure plummeted, her breathing and heart function stopped.

— Michael Collins, USA Today, 30 Aug. 2026

Definition of severe

Adjective

Amid a national cinema that has become internationally recognized for perverse plotting and deadpan absurdism, writer-director Alexis Alexiou‘s third feature stands out for its stark storytelling and earnest emotional intensity.

— Guy Lodge, Variety, 30 Aug. 2026
But there’s also a subtle rejection of the earnest wokeness of years past.

— Inkoo Kang, New Yorker, 27 Aug. 2026

Definition of earnest

Adjective

Applying high-temperature treatment to large magnet components, however, would present major engineering challenges.

— Aamir Khollam, Interesting Engineering, 5 Sep. 2026
The Italian supermodel attended this major film event wearing a dress from the Chanel Cruise 2026–2027 collection.

— Giacomo Aricò, Vogue, 5 Sep. 2026

Definition of major

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 5 Sep. 2026.

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Synonyms of serious

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