General terms:
* Isthmus: This is the most common term for a narrow strip of land connecting two larger landmasses and separating two bodies of water. Examples include the Isthmus of Panama and the Isthmus of Suez.
* Neck: This is a general term for a narrow connecting piece of land, often used for a narrow part of a peninsula.
* Strip: This is a more general term that can be used for any narrow piece of land.
* Spit: This is a narrow strip of land that projects out into a body of water, often formed by the deposition of sand or gravel.
More specific terms:
* Tombolo: This is a narrow strip of land that connects an island to the mainland, often formed by the deposition of sand or gravel.
* Sandbar: This is a narrow, submerged ridge of sand or gravel that can sometimes emerge above the water level.
* Promontory: This is a high, rocky point of land that projects out into the sea, often with a narrow neck connecting it to the mainland.
* Headland: This is a point of land that extends out into the sea, often with steep cliffs.
The best term to use will depend on the specific characteristics of the narrow stretch of land in question.
