territorial waters

American  

[ter-i-tawr-ee-uhl waw-terz, wot-erz] / ˈtɛr ɪˌtɔr i əl ˈwɔ tərz, ˈwɒt ərz /

plural noun

International Law.

1. the waters of a coastal state or nation that are regarded as under the jurisdiction of the state or nation, traditionally within 3 miles (4.8 km) of the shore, but with claims by certain coastal nations that have extended to 12 or even 200 miles (20 or 322 km).

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territorial waters British  

plural noun

1. the waters over which a nation exercises jurisdiction and control

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Etymology

Origin of territorial waters

First recorded in 1870–75

Example Sentences

China says it is acting inside its territorial waters.

From The Wall Street Journal • Apr. 11, 2026

By forcing vessels to reroute, ships are entering Iran's territorial waters and Tehran's maritime rules, says Michelle Wiese Bockmann from Windward Maritime Analytics.

From BBC • Mar. 19, 2026

Also, CNN reported that 38 crew members were rescued after a suspected Iranian attack set two foreign tankers ablaze in Iraqi territorial waters, citing the head of Iraq’s ports company.

From MarketWatch • Mar. 11, 2026

Herath said the ship was outside Sri Lanka’s territorial waters.

From The Wall Street Journal • Mar. 4, 2026

At eight, we reach six fathoms—the limit of American territorial waters.

From Merchantmen-at-arms : the British merchants' service in the war by Bone, David W. (David William)