n.
Function: adjective
Synonyms: SERIOUS 1, grave, no-nonsense, sedate, sober, sobersided, solemn, somber, staid, weighty
Related Words: ardent, enthusiastic, passionate, pressing, warm, zealous; assiduous, busy, diligent, industrious, perseverant, sedulous; sincere, wholehearted, whole-souled
Contrasted Words: buoyant, effervescent, elastic, flippant, light
Antonyms: frivolous