The definition of placid is calm or quiet.(adjective)
An example of placid is a still lake in the middle of a forest.
See placid in Webster's New World College Dictionary
Origin: L placidus, akin to placere, to please
See placid in American Heritage Dictionary 4
Origin: Latin placidus
Origin: , from placēre, to please; see plāk-1 in Indo-European roots.
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