The name "Zeta" derives from an early root meaning "harvest" or "grain" (modern words žetva and žito).
Zeta River is the most significant tributary of Morača. Perućica Hydroelectric power plant near Nikšić (307 MW, 970 GWh) uses the waters of Zeta River to generate power. After that, river meanders through Bjelopavlići Valley, until it empties into Morača a few miles north of Podgorica.