The branch of international law that deals with territorial and international waters or with shipping or with ocean fishery etc. WordNet 3.0 & Open English WordNet

Admiralty law or maritime law is a body of law that governs nautical issues and private maritime disputes. Wikipedia

The totality of applicable law for the oceans and their use Wikidata

That system of law which particularly relates to marine commerce and navigation, to business transacted at sea or relating to navigation, to ships and shipping, to seamen, to the transportation of persons and property by sea, and to marine affairs generally. OmegaWiki

The area of law that deals with ships at sea and the rights of sailors, passengers, and owners of cargo. OmegaWiki

Area of law that deals with ships at sea. Wiktionary (translation)

The body of law concerning international trade on the high seas. Wiktionary