Simple Definition of serious
: 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
Full Definition of serious
1 : thoughtful or subdued in appearance or manner : sober <a quiet, serious girl>
2a : requiring much thought or work <serious study>b : of or relating to a matter of importance <a serious play>
4a : 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>
Examples of serious
“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.
Origin 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
Medical Definition of serious
: having important or dangerous possible consequences <a serious injury>
Seen and Heard
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