a. [ L. piacularis: cf. F. piaculaire. ] 1. Expiatory; atoning. Sir G. C. Lewis. [ 1913 Webster ]
2. Requiring expiation; criminal; atrociously bad. “Piacular pollution.” De Quincey. [ 1913 Webster ]
n. The quality or state of being piacular; criminality; wickedness. De Quincey. [ 1913 Webster ]