pĭo, āvi, ātum, 1, v. a. [pius].
I To seek to appease , to appease , propitiate by sacrifice (syn. place).—
B Lit.: Silvanum lacte piabant, Hor. Ep. 2, 1, 143: ossa, Verg. A. 6, 379: busta (i.e. Manes), Ov. M. 13, 515: Janus Agonali luce piandus erit, id. F. 1, 318.—
II Transf.
A To honor with religious rites , to celebrate : ubi piem Pietatem, Plaut. As. 3, 1, 3: aras ture, Prop. 3, 10 (4, 9), 19: in magicis astra piare focis, to perform sacred rites , id. 1, 1, 20.—
B To purify with sacred rites (syn.: procuro, lustro): si quid tibi piandum fuisset, Cic. Dom. 51.—
C To make or seek to make good , to atone for , expiate : damna, Ov. A. A. 3, 160: mors morte pianda est, id. M. 8, 483: fulmen, to avert by sacrifice the misfortune portended by lightning , id. F. 3, 291: nefas triste, to atone for , avert the penalty , Verg. A. 2, 184; Ov. H. 19, 194: cometes terrificum sidus, ac non leviter piatum, Plin. 2, 25, 23, § 92.—
D To punish , avenge : culpam morte, Verg. A. 2, 140: grande nefas et morte piandum, Juv. 13, 54.—
E To free from madness , Fest. p. 213 Müll.: jube te piari de meā pecuniā: nam ego quidem insanum te esse certo scio, Plaut. Men. 2, 2, 17; so id. ib. 3, 2, 51.