Found 2 items, similar to mare liberum.
English → English (WordNet) Definition: mare liberum mare liberum n : (free sea) a navigable body of water to which all nations have equal access
English → English (gcide) Definition: mare liberum mare liberum \mare liberum\ n. [L., free sea.] A navigable body of water to which all nations have equal access; the opposite of mare clausum. [WordNet 1.5]