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pĭācŭlāris, e, adj. [piaculum], atoning, expiatory, piacular (rare; not in Cic.): hostia, Varr. L. L. 6, § 30 Müll.: sacrificia, sinofferings, Liv. 1, 26; also absol.: ut piacularia Junoni fierent, id. 42, 3: piacularia auspicia appellabant, quae sacrificantibus tristia portendebant, cum aut hostia ab arā effugisset, aut percussa mugitum dedisset, aut in aliam partem corporis quam oporteret cecidisset, Paul. ex Fest. p. 244 Müll.: piacularis porta appellatur propter aliqua piacula, quae ibidem fiebant, Fest. p. 212 Müll.; Plin. Ep. 3, 9, 9.
Comic., transf., Plaut. Ep. 1, 2, 36.
Adv.: pĭācŭlārĭ-ter, sinfully: negare, Tert. Pud. 22 (al. peculiariter).