Black's Law Dictionary, Sixth Edition, p. 1387:

Situs.  Lat.  Situation; location; e.g. location or place of crime or business.  Site; position; the place where a thing is considered, for example, with reference to jurisdiction over it, or the right or power to tax it.  It imports fixedness of location.  Situs of property, for tax purposes, is determined by whether the taxing state has sufficient contact with the personal property sought to be taxed to justify in in fairness the particular tax.  Town of Cady v. Alexander Const. Co., 12 Wis.2d 236, 107 N.W.2d 267, 270.

[Black's Law Dictionary, Sixth Edition, p. 1387]