serious (adj.)

early 15c., "arranged in sequence, continuous" (a sense now obsolete); mid-15c., of persons, "expressing earnest purpose or thought, resolute," from Old French serios "grave, earnest" (14c., Modern French sérieux) and directly from Late Latin seriosus, from Latin serius "weighty, important, grave."

This is probably from a PIE root *sehro- "slow, heavy" (source also of Lithuanian sveriu, sverti "to weigh, lift," svarus "heavy, weighty;" Old English swær "heavy," German schwer "heavy," Gothic swers "honored, esteemed," literally "weighty").

According to Middle English Compendium, two sets of Latin stems "seem to have fallen together" in Medieval Latin: ser- (as in series, serere) and sēr- (as in sērius, sēriōsus, etc.), perhaps through semantic overlap, which accounts for the earlier Middle English record of the word, which seems to belong to the first stem.

As "in earnest, not pretending or jesting," from 1712; in reference to of music, theater, etc., "dealing with grave matters" by 1762. The meaning "attended with danger, giving grounds for alarm" is from 1800. Serious-minded is attested by 1845.

updated on May 25, 2022

Definitions of serious from WordNet

serious (adj.)
concerned with work or important matters rather than play or trivialities;
a serious young man
are you serious or joking?
a serious student of history
Don't be so serious!
gave me a serious look
a serious attempt to learn to ski
serious (adj.)
of great consequence;
marriage is a serious matter
serious (adj.)
causing fear or anxiety by threatening great harm;
a serious wound
a serious turn of events
Synonyms: dangerous / grave / grievous / severe / life-threatening
serious (adj.)
appealing to the mind;
a serious book
Synonyms: good
serious (adj.)
requiring effort or concentration; complex and not easy to answer or solve;
raised serious objections to the proposal
the plan has a serious flaw
serious (adj.)
completely lacking in playfulness;
Synonyms: unplayful / sober
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