Lewis Short
(verb) : sub-tĕro, trīvi, trītum, 3
* To rub off or wear away underneath; to rub, bruise, or grind to pieces (rare; not in Cic.): boves ne pedes subterant,Cato, R. R. 72; so, pedes,Col. 6, 15, 2; Plin. 28, 16, 62, § 221: ungulas,Plaut. As. 2, 2, 73: jumenta cito subteruntur,Sen. Ep. 51, 9: salis sextarium subterito, et subtritum, etc.,pound, triturate,Col. 12, 5, 1: caepam aridam,id. 12, 5, 56; 2, 10, 25; Plin. 20, 20, 82, § 218; 30, 9, 23, § 80.
Charlton T. Lewis, Charles Short, A Latin Dictionary