The terms international waters or trans-boundary 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. Oceans, seas, and waters outside of national jurisdiction are also referred to as the high seas or, in Latin, mare liberum (meaning free sea).