'Placid' definitions:

Definition of 'placid'

From: WordNet
adjective
(of a body of water) free from disturbance by heavy waves; "a ribbon of sand between the angry sea and the placid bay"; "the quiet waters of a lagoon"; "a lake of tranquil blue water reflecting a tranquil blue sky"; "a smooth channel crossing"; "scarcely a ripple on the still water"; "unruffled water" [syn: placid, quiet, still, tranquil, smooth, unruffled]
adjective
Not easily irritated; "an equable temper"; "not everyone shared his placid temperament"; "remained placid despite the repeated delays" [syn: equable, even-tempered, good- tempered, placid]

Definition of 'Placid'

From: GCIDE
  • Placid \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. [1913 Webster]