Law that becomes binding on nations through general acceptance as a matter of legal obligation. When enough states have begun to behave as though some principle is law, it becomes law "by use [..]

The portion of international law that has developed over time through custom and usage, rather than formal agreement. Contrasts with conventional international law.

Law that becomes binding on states although it is not written, but rather adhered to out of custom; when enough states have begun to behave as though something is law, it becomes law "by use& [..]

Customary international law refers to those aspects of international law that becomes binding on nations through general acceptance as a matter of legal obligation. Those principles of law that states [..]

practice that is recognised in law on the basis of custom and tradition. In order to become customary international law a practice has to fulfil two elements: uniform and consistent state practice ove [..]