serious

adjective se·ri·ous \ ˈsir-ē-əs \

Definition of serious

1 :thoughtful or subdued in appearance or manner :sober

a quiet, serious girl

2 a :requiring much thought or work

serious study

b :of or relating to a matter of importance

a serious play

3 a :not joking or trifling :being in earnest

a serious question

b archaic :pious

c :deeply interested :devoted

a serious musician

4 a :not easily answered or solved

serious objections

b :having important or dangerous possible consequences

a serious injury

5 :excessive or impressive in quality, quantity, extent, or degree

serious stereo equipment

making serious money

serious drinking

—

seriousness

noun

See serious defined for English-language learners

See serious defined for kids

Examples of serious in a Sentence

“You sound terrible.” “It's just a bad cold. Nothing serious.”
For my brother, not going to college was a serious mistake.
Crime is a serious problem in this neighborhood.
The team is a serious contender for the championship.
If you want to quit smoking, you have to make a serious effort.
They had a serious conversation about their relationship.
a serious novel about modern life
The story raises serious questions about our system of justice.
Dog shows are a serious business.
She is a serious cyclist who rides 200 miles each week.

Recent Examples of serious from the Web

Meanwhile, Oetker told investors attending Stada’s annual shareholder meeting in Frankfurt that an investigation into former top executives has found serious wrongdoing.

— eyk henning, Bloomberg.com, "Stada Is Close to Naming Pharma Veteran Albrecht New CEO," 30 Aug. 2017
But beneath the drama of the diamond is a more serious question that still has no clear answer: How should modern nations deal with a colonial legacy of looting?

— lorraine boissoneault, Smithsonian, "The True Story of the Koh-i-Noor Diamond—And Why the British Won’t Give It Back," 30 Aug. 2017
This is about a young, valuable, and bright life that may need serious help.

— sam mellinger, kansascity, "Why Duffy’s DUI shouldn’t be washed away because of well-earned goodwill and popularity," 29 Aug. 2017
Jon jumps in to try to convey how serious the threat of the army of the dead is.

— elyse roth, Glamour, "'Game of Thrones' Season 7 Finale Recap: A Major Death, That Jon and Daenerys Thing Happened, and So Much More," 28 Aug. 2017
The 25-mile ride around the San Diego Bay attracted serious cyclists and casual riders, and families and cycling clubs and teams.

— joshua stewart, sandiegouniontribune.com, "3,400 bikes, including some weird ones, cycle around the San Diego Bay," 27 Aug. 2017
But the idea that Trump would end an active investigation to benefit a political ally raised the specter of a more serious offense.

— benjamin hart, Daily Intelligencer, "Trump Reportedly Wanted to Kill Arpaio Investigation Before Conviction," 27 Aug. 2017
Windows 95 machines may seem laughably old, but computers that run antiquated operating systems are a serious problem.

— david grossman, Popular Mechanics, "22 Years Later, Internet-Connected Computers Are Still Running Windows 95," 24 Aug. 2017
Summers's hobby turned serious when his lab finally got its own CT scanner in 2015.

— ryan cross, Science | AAAS, "New 3D scanning campaign will reveal 20,000 animals in stunning detail," 24 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'serious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of serious

Middle English seryows, from Anglo-French or Late Latin; Anglo-French serious, from Late Latin seriosus, alteration of Latin serius weighty, serious; probably akin to Old English swǣr heavy, sad

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First Known Use: 15th century

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serious Synonyms

Synonyms

earnest, grave, humorless, no-nonsense, po-faced [British], sedate, severe, sober, sobersided, solemn, staid, uncomic, unsmiling, weighty

Antonyms

facetious, flip, flippant, humorous, jesting, jocular, joking, kittenish, ludic, playful

Related Words

harsh, stern, strict; businesslike, professional; dignified, distinguished, elevated, serious-minded; gloomy, grim

Near Antonyms

antic, comic, comical, droll, farcical, funny, hilarious, hysterical (also hysteric), laughable, light, light-headed, ludicrous, ridiculous, riotous, risible, screaming, sidesplitting, uproarious; featherbrained, flighty, frivolous, goofy, harebrained, lighthearted, puerile, scatterbrained; absurd, asinine, balmy, brainless, cockeyed, crazy, cuckoo, daffy, daft, dotty, fatuous, foolish, half-witted, insane, jerky, kooky (also kookie), loony (also looney), lunatic, mad, nonsensical, nutty, preposterous, sappy, screwball, senseless, silly, unwise, wacky (also whacky), weak-minded, witless, zany

Synonym Discussion of serious

serious, grave, solemn, sedate, staid, sober, earnest mean not light or frivolous. serious implies a concern for what really matters.

- a serious play about social injustice

grave implies both seriousness and dignity in expression or attitude.

- read the proclamation in a grave voice

solemn suggests an impressive gravity utterly free from levity.

- a sad and solemn occasion

sedate implies a composed and decorous seriousness.

- remained sedate amid the commotion

staid suggests a settled, accustomed sedateness and prim self-restraint.

- a quiet and staid community

sober stresses seriousness of purpose and absence of levity or frivolity.

- a sober look at the state of our schools

earnest suggests sincerity or often zealousness of purpose.

- an earnest reformer

SERIOUS Defined for English Language Learners

serious

adjective

Definition of serious for English Language Learners

: having an important or dangerous possible result
: involving or deserving a lot of thought, attention, or work
: giving a lot of attention or energy to something

SERIOUS Defined for Kids

serious

adjective se·ri·ous \ ˈsir-ē-əs \

Definition of serious for Students

1 :not joking or funny

a serious drama

2 :being such as to cause distress or harm

a serious accident

3 :thoughtful or quiet in appearance or manner

a serious person

4 :requiring much thought or work

a serious task

—

seriousness

noun

Synonym Discussion of serious

serious, solemn, and earnest mean not funny or not playful. serious means being concerned or seeming to be concerned about really important things.

- He's a serious student.

solemn is used for dignity along with complete seriousness.

- The preacher is always very solemn.

earnest means that someone is sincere and has serious intentions.

- She's an earnest, diligent student.

Medical Dictionary

serious

adjective se·ri·ous \ ˈsir-ē-əs \

medical Definition of serious

:having important or dangerous possible consequences

a serious injury

Learn More about serious

See words that rhyme with serious Thesaurus: All synonyms and antonyms for serious Spanish Central: Translation of serious Nglish: Translation of serious for Spanish speakers Britannica English: Translation of serious for Arabic speakers

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Origin and Etymology of serious

serious Synonyms

Synonyms

Antonyms

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SERIOUS Defined for English Language Learners

serious

Definition of serious for English Language Learners

SERIOUS Defined for Kids

serious

Definition of serious for Students

seriousness

Synonym Discussion of serious

Medical Dictionary

serious

medical Definition of serious

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