The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed regional seas and estuaries, rivers, lakes, groundwater systems (aquifers), and wetlands.
"International waters" is not a defined term in international law. It is an informal term, which sometimes refers to waters beyond the "territorial sea" of any country. In other words, "international waters" is sometimes used as an informal synonym for the more formal term high seas or, in Latin, mare liberum (meaning free sea).
en
