Lewis & Short

1. pīla, ae, f. [perh. for pisula, from root pis-; v. pinso, piso], a mortar (syn. mortarium): pila, ubi triticum pinsant, Cato, R. R. 14; Ov. Ib. 573: zeae granum tunditur in pilā ligneā, Plin. 18, 11, 29, § 112: si contuderis stultum in pilā, Vulg. Prov. 27, 22: sal sordidum in pilā pisatum, Paul. ex Fest. p. 158 Müll.