An isthmus.
That would be an isthmus.
Straits are a narrow strip of water connecting two large bodies of water.
a paradox
It is called an isthmus.
A strip of land connecting two large landmasses is called an isthmus. It serves as a narrow bridge between two larger bodies of land, often connecting two continents or two sections of a continent.
Strait Source: http://worldlandforms.com/landforms/list-of-all-landforms/
A narrow landform connecting two large pieces of land is called an isthmus. It is typically a narrow strip of land with water on both sides, connecting two larger landmasses or separating two bodies of water.
isthmus - When a narrow strip connects two land masses. If it projects into ocean without connecting any land mass, it is called peninsula.
a strait is a narrow passage of water connecting two larger bodies of water. An isthmus is a narrow strip of land, bordered by water, connecting two larger bodies of land
isthmus
a narrow strip of land, bordered on both sides by water, connecting two larger bodies of land.
a narrow strip of land, bordered on both sides by water, connecting two larger bodies of land