What is Sovereign Power?

Legal Definition
That power in a state to which none other is superior or equal, and which includes all the specific powers which are necessary to accomplish the legitimate ends and purposes of government See Boggs v. Merced Min. Co., 14 Cal. 309: Donnelly v. Decker, 58 Wis, 461, 17 N. W. 389, 46 Am. Rep. 637; Com. v. Alger, 7 Cush. (Mass.) 81.
-- Black's Law Dictionary