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Dictionary.com

not serious

ADJECTIVE
facetious
Synonyms
WEAK
amusing blithe capering clever comic comical droll dry fanciful farcical flip flippant frivolous funny humorous indecorous ironic irreverent jesting jocose jocular joking joshing laughable ludicrous merry playful pleasant pulling one's leg punning putting one on ridiculous salty sarcastic satirical smart sportive sprightly waggish whimsical wisecracking witty wry
Antonyms
WEAK
formal grave serious unfunny
ADJECTIVE
frivolous
Synonyms
STRONGEST
foolish idiotic impractical petty pointless senseless
WEAK
barmy childish dizzy empty-headed facetious featherbrained flighty flip flippant gay giddy harebrained idle ill-considered juvenile light light-minded minor niggling nonserious paltry peripheral playful puerile scatterbrained shallow sportive superficial tongue-in-cheek unimportant unprofound volatile whimsical
Antonyms
STRONGEST
intelligent sensible wise
WEAK
grave mature serious solemn thoughtful
ADJECTIVE
idle
Synonyms
STRONGEST
empty unproductive useless
STRONG
hollow rambling
WEAK
abortive bootless frivolous fruitless futile groundless insignificant irrelevant nugatory of no avail otiose pointless superficial trivial unavailing unhelpful unnecessary unsuccessful vain
Antonyms
WEAK
active ambitious busy diligent effective employed hustling important productive used working worthwhile
ADJECTIVE
tongue-in-cheek
Synonyms
STRONGEST
amusing comic flippant humorous ironic irreverent jocular joking playful sarcastic satirical whimsical
STRONG
jokingly
WEAK
blithe clever comical dry facetious farcical flip funny in fun in jest ironical jesting joshing kiddingly laughable pulling one's leg putting one on smart wisecracking witty
Antonyms
STRONGEST
respectful reverent serious unfunny
ADJECTIVE
venial
Synonyms
WEAK
all right allowable defensible excusable explainable forgivable justifiable minor not too bad okay permissible slight tolerable trivial understandable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Defense Secretary Pete Hegseth said Iran’s latest attacks were not serious enough to break the cease-fire.

From MarketWatch • May 5, 2026

Dorset Police previously said the rider and a pillion passenger left the scene, leaving the woman with injuries that were not serious.

From BBC • Feb. 3, 2026

“I love you,” he said, “but you are not serious people.”

From Salon • Dec. 9, 2025

Rodrigo Bentancur could consider himself fortunate to escape with a booking after the Tottenham midfielder's ugly challenge on Reece James was deemed "not serious foul play".

From Barron's • Nov. 1, 2025

He might think I’m not serious about writing—not brave enough to be open to feedback.

From "Keeping Pace" by Laurie Morrison