Webster’s Revised Unabridged Dictionary · 1913
Staid
Staid (stād), imp. & p. p. of Stay.
Staid, a. [From Stay to stop.] Sober; grave; steady; sedate; composed; regular; not wild, volatile, or fanciful. "Sober and staid persons." Addison.
O'erlaid with black, staid Wisdom's hue. Milton.
Syn. — Sober; grave; steady; steadfast; composed; regular; sedate.