In international law. That portion of the territory of any country which lies close along “the border line of another country, and so “fronts” or faces it The term means something more than the boundary line itself, and includes a tract or strip of country, of indefinite extent, contiguous to the line. Stoughton v. Mott 15 Vt. 169.
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TheLaw.com Law Dictionary & Black's Law Dictionary 2nd Ed.