The term nipru seems to be formed from the root napar, which is in Syriac to "pursue," to "make to flee," and which has in Assyrian nearly the same meaning.
Thus Bil-Nipru would be aptly translated as "the Hunter Lord," or "the god presiding over the chase," while, at the same time, it might combine the meaning of "the Conquering Lord" or "the Great Conqueror." On these grounds it is reasonable to conclude that we have, in this instance, an admixture of hero-worship in the Chaldaean religion.
Bil-Nipru is probably the Biblical Nimrod, the original founder of the monarchy, the "mighty hunter" and conqueror.

At the same time, however, that he is this hero deified, he represents also, as the second god of the first Triad, the classical Jupiter.

He is "the supreme," "the father of the gods," "the procreator," "the Lord," _par excellence,_ "the king of all the spirits," "the lord of the world," and again, "the lord of all the countries." There is some question whether he is altogether to be identified with the Belus of the Greek writers, who in certain respects rather corresponds to Merodach.

When Belus, however, is called the first king, the founder of the empire, or the builder of Babylon, it seems necessary to understand Bil-Nipru or Bel-Nimrod.

Nimrod, we know, built Babylon; and Babylon was called in Assyrian times "the city of Bil-Nipru," while its famous defences--the outer and the inner wall--were known, even under Nebuchadnezzar, by the name of the same god .-- Nimrod, again, was certainly the founder of the kingdom; and, therefore, if Bil-Nipru is his representative, he would be Belus under that point of view.
The chief seat of Bel-Nimrod's worship was undoubtedly Nipur (Niffer) or Calneh.