inland sea; enclosed sea; inlet
Refers to a sea largely surrounded by land, such as the Caspian Sea or the Seto Inland Sea. Used in geographical contexts.
An inland sea is a sea surrounded by continents.
Caspian Sea
Specifically refers to the Caspian Sea, the world's largest inland body of water. Often used with the cross-reference カスピ海.
See also: カスピ海
The Caspian Sea (裏海) is located on the border between Europe and Asia.