a surname of Jupiter, which is probably derived from ferire, to strike; for persons who took an oath called upon Jupiter, if they swore falsely, to strike them as they struck the victim they sacrificed to him. (Fest. s. v. Lapidem Silicem.) Others derived it from ferre, because he was the giver of peace, or because people dedicated (ferebant) to him spolia opima. (Fest. s. v. Feretrius; Liv. 1.10; Propert. 4.10. 46; comp. JUPITER.)
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890