serious, grave, solemn, sedate, staid, sober, earnest mean not light or frivolous. serious implies a concern for what really matters.

Please don't laugh - I'm being serious. He was wearing a very serious expression and I knew something was wrong. On the surface it's a very funny novel but it does have a more serious underlying theme.

SERIOUS definition: of, showing, or characterized by deep thought. See examples of serious used in a sentence.

1. of, showing, or characterized by deep thought. 2. grave or somber, as in character, disposition, or mood.

Discover everything about the word "SERIOUS" in English: meanings, translations, synonyms, pronunciations, examples, and grammar insights - all in one comprehensive guide.

being in earnest; sincere; not trifling: His interest was serious. requiring thought, concentration, or application: serious reading; a serious task. weighty or important: a serious book; Marriage is a …

These adjectives refer to manner, appearance, disposition, or acts marked by absorption in thought, pressing concerns, or significant work. Serious implies a concern with responsibility and work as …

Dec 4, 2025 · seriousness (countable and uncountable, plural seriousnesses) The state or quality of being serious. synonyms, antonyms quotations Synonyms: earnestness, seriosity (uncommon) …

Definition of serious adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Some common synonyms of serious are earnest, grave, sedate, sober, solemn, and staid. While all these words mean "not light or frivolous," serious implies a concern for what really matters.