General:
* Island: A piece of land completely surrounded by water.
* Peninsula: A piece of land almost completely surrounded by water, with a narrow connection to a larger landmass.
Specific:
* Lagoon: A shallow body of water separated from the sea by a barrier island or reef.
* Bay: A large body of water partially enclosed by land.
* Gulf: A large bay, often with a wider opening to the sea.
* Sound: A narrow body of water, often between an island and the mainland.
* Estuary: A body of water where freshwater from a river mixes with saltwater from the sea.
Other options:
* Archipelago: A group of islands.
* Sea: A large body of salt water.
* Ocean: The largest body of salt water.
The best word to use depends on the specific size, shape, and location of the area in question.
