[se.ri.ous] adj [ME seryows, fr. MF or LL; MF serieux, fr. LL seriosus, alter. of L serius weighty, serious; prob. akin to OE swaer heavy, sad] (15c) 1: thoughtful or subdued in appearance or manner: sober
2. a: requiring much thought or work "~ study" b: of or relating to a matter of importance "a ~ play" 3 a: not joking or trifling: being in earnest b archaic: pious c: deeply interested: devoted "a ~ musician"
4. a: not easily answered or solved "~ objections" b: having important or dangerous possible consequences "a ~ injury"
5: excessive or impressive in quantity, extent, or degree: considerable "making ~ money" "~ drinking" -- se.ri.ous.ness n syn 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".