adjective se·ri·ous \ˈsir-ē-əs\

Definition of serious

  1. 1 :  thoughtful or subdued in appearance or manner :  sober a quiet, serious girl

  2. 2a :  requiring much thought or work serious studyb :  of or relating to a matter of importance a serious play

  3. 3a :  not joking or trifling :  being in earnest a serious questionb archaic :  piousc :  deeply interested :  devoted a serious musician

  4. 4a :  not easily answered or solved serious objectionsb :  having important or dangerous possible consequences a serious injury

  5. 5 :  excessive or impressive in quality, quantity, extent, or degree serious stereo equipment making serious money serious drinking



Examples of serious in a sentence

  1. You sound terrible. It's just a bad cold. Nothing serious.

  2. For my brother, not going to college was a serious mistake.

  3. Crime is a serious problem in this neighborhood.

  4. The team is a serious contender for the championship.

  5. If you want to quit smoking, you have to make a serious effort.

  6. They had a serious conversation about their relationship.

  7. a serious novel about modern life

  8. The story raises serious questions about our system of justice.

  9. Dog shows are a serious business.

  10. She is a serious cyclist who rides 200 miles each week.

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

First Known Use: 15th century

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


adjective se·ri·ous \ˈsir-ē-əs\

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


adjective se·ri·ous \ˈsir-ē-əs\

Definition of serious for Students

  1. 1 :  not joking or funny a serious drama

  2. 2 :  being such as to cause distress or harm a serious accident

  3. 3 :  thoughtful or quiet in appearance or manner a serious person

  4. 4 :  requiring much thought or work a serious task



Medical Dictionary


adjective se·ri·ous \ˈsir-ē-əs\

Medical Definition of serious

  1. :  having important or dangerous possible consequences a serious injury

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