noun

• An island in Nagasaki, Japan, between the Home Islands and Korea, now divided by early modern canals.
• A city in Nagasaki, Japan, coterminous with the main island of Tsushima.
• An archipelago in Nagasaki, Japan, surrounding the main island of Tsushima.
• A strait in Japan, between Tsushima Island and the Home Islands, the location of a major 1905 battle in the Russo-Japanese War.