Meaning of SERIOUS in English

SERIOUS

adj.1 thoughtful, earnest, sober, sedate, responsible, not reckless or given to trifling (has a serious air; a serious young person).

2 important, demanding consideration (this is a serious matter).

3 not slight or negligible (a serious injury; a serious offence).

4 sincere, in earnest, not ironical or joking (are you serious?).

5 (of music and literature) not merely for amusement (opp. LIGHT(2) 5a).

6 not perfunctory (serious thought).

7 not to be trifled with (a serious opponent).

8 concerned with religion or ethics (serious subjects).

Derivatives:

seriousness n.

Etymology: ME f. OF serieux or LL seriosus f. L serius

Oxford English vocab.      Оксфордский английский словарь.