isthmus

Etymology

Borrowing from Latin isthmus (“a strip of land between two seas”), from Ancient Greek ῐ̓σθμός (isthmós, “neck, narrow passage”), possibly from εἶμῐ (eîmi, “to go”). Cognate to Old Norse eið (“isthmus”).

noun

1. A narrow strip of land, bordered on both sides by water, and connecting two larger landmasses.
2. (anatomy) Any such narrow part connecting two larger structures.
3. (graph theory) An edge in a graph whose deletion increases the number of connected components of the graph.