treaty

Definition from Nolo’s Plain-English Law Dictionary

A pact between nations that, if entered into by the United States through its Executive Branch, must be approved by two-thirds of the Senate under Article II, Section 2 of the Constitution. Presidents sometimes get around this requirement by entering into "Executive Agreements" with leaders of other countries; these are mutual understandings rather than enforceable treaties.

Definition provided by Nolo’s Plain-English Law Dictionary.