Serious

/ˈsɪəriəs/
B1

Definition, CEFR level B1, pronunciation, examples, and quiz.

Listen pronunciation

adjectiveImportant, dangerous, or needing careful thought.

adjectiveNot joking or playful.

Extra definitions

adjectiveImportant and needing attention.

adjectiveHaving a bad or dangerous effect.

adjectiveWithout humor or expression of happiness; grave in manner or disposition.

The accident caused serious damage.
We need a serious discussion.
She is serious about learning.
Synonyms:
None
Antonyms:
None

From Middle English seryows, from Old French serieux, from Medieval Latin sēriōsus, an extension of Latin sērius (“grave, earnest, serious”), possibly ultimately from Proto-Indo-European *swer- (“heavy”). (If this root is correct, cognate with German schwer (“heavy, difficult, severe”), Old English swǣr (“heavy, grave, grievous”). More at swear, sweer. However, see sērius for an alternative derivation of the Latin.)

“The only time I walk out on singin' is when there's muckin' about and youse don't take it serious.” — 1957, Ray Lawler, Summer of the Seventeenth Doll, Sydney: Fontana Books, published 1974, page 68:
CEFR Practice Quiz
The accident caused ____ damage.

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