Plac"id (?), a. [L. placidus,
originally, pleasing, mild, from placere to please: cf. F.
placide. See Please.] Pleased; contented;
unruffied; undisturbed; serene; peaceful; tranquil; quiet;
gentle. "That placid aspect and meek regard."
Milton. "Sleeping . . . the placid sleep of infancy."
Macaulay.