Lewis Short
pĭātrix (noun F) : piator
* She that appeases the gods by a sacrifice: piatrix dicebatur sacerdos, quae expiare erat solita, quam quidam simulatricem, alii sagam, alii expiatricem vocant,Fest. p. 213 Müll. (in Plaut. Mil. 3, 1, 101, read plicatricem).
Charlton T. Lewis, Charles Short, A Latin Dictionary