(Derived from the Lat. pecus, 'livestock': Varro, Ling. 5,92, cf. ) in Lat., designates assets, originally in livestock, then generally money. The etymology shows that in Rome livestock used as currency preceded metal money. In the 4th cent. AD pecunia designated a coin, or piece of money (Eutr. 9,14), sometimes with specification of the metal (Aug. Civ. 4,21; 4,28) or in a limited sense, copper money (SHA Sev. 33,3).
1 Walde/Hofmann, s.v. P., vol. 2, 272.
Schrötter, s.v. P., 492.