isthmus
ISS-mus
A narrow strip of land connecting two larger landmasses, with water on both sides. The Isthmus of Panama connects the Americas; the Isthmus of Corinth connects mainland Greece to the Peloponnese. An isthmus is a thread: cut it and two worlds separate.
Etymology
Latin, from Greek isthmos, a narrow passage. The word has been in English since antiquity.
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