Pertero, pérteris, pen. cor. pertríui, pertiîtum, pen. prod. pertérere. Colum. To rub or frote a thing: to frote a sunder: to rub in peeces: to breake in small crummes.Ianuam lima perterunt.Plaut.They file a sunder the gate.
Lewis and Short: Latin dictionary
per-tĕro, no perf., trītum, 3, v. a., to rub, bruise, or pound to pieces: myrti bacam, Col. 12, 38, 7: uva pertrita, id. 8, 5, 21.