a. [ Poly- + acid. ] (Chem.) Capable of neutralizing, or of combining with, several molecules of a monobasic acid; having more than one hydrogen atom capable of being replaced by acid radicals; -- said of certain bases;
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. [ 1913 Webster ]
n. [ L. placiditas: cf. F. placidité. ] The quality or state of being placid; calmness; serenity. Hawthorne. [ 1913 Webster ]
adv. In a placid manner. [ 1913 Webster ]
n. The quality or state of being placid. [ 1913 Webster ]
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. [ 1913 Webster ]
n. [ L. placiditas: cf. F. placidité. ] The quality or state of being placid; calmness; serenity. Hawthorne. [ 1913 Webster ]
adv. In a placid manner. [ 1913 Webster ]
n. The quality or state of being placid. [ 1913 Webster ]