Serious \Se"ri*ous\, a. [L. serius: cf. F. s['e]rieux, LL. seriosus.]

1. Grave in manner or disposition; earnest; thoughtful; solemn; not light, gay, or volatile.

He is always serious, yet there is about his manner a graceful ease. --Macaulay.

2. Really intending what is said; being in earnest; not jesting or deceiving. --Beaconsfield.

3. Important; weighty; not trifling; grave.

The holy Scriptures bring to our ears the most serious things in the world. --Young.

4. Hence, giving rise to apprehension; attended with danger; as, a serious injury.

Syn: Grave; solemn; earnest; sedate; important; weighty. See Grave. -- Se"ri*ous*ly, adv. -- Se"ri*ous*ness, n.

Source: Webster's Revised Unabridged Dictionary (1913)