The title generally applied to the chief men of the state. The "princes of the provinces" (1 Kings 20:14) were the governors or lord-lieutenants of the provinces. So also the "princes" mentioned in Dan. 6:1, 3, 4, 6, 7 were the officers who administered the affairs of the provinces; the "satraps" (as rendered in R.V.). These are also called "lieutenants" (Esther 3:12; 8:9; R.V., "satraps"). The promised Saviour is called by Daniel (9:25) "Messiah the Prince" (Heb. nagid); compare Acts 3:15; 5:31. The angel Micheal is called (Dan. 12:1) a "prince" (Heb. sar, whence "Sarah," the "princes").
Easton's Bible Dictionary. M.G. Easton. 1897.