| a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
isthmus isth·mus (ĭs'məs)
n. pl. isth·mus·es or isth·mi (-mī')
A constriction or narrow passage connecting two larger parts of an organ or other anatomical structure.
| isthmus (ĭs'məs) Pronunciation Key
Plural isthmuses or isthmi (ĭs'mī') A narrow strip of land connecting two larger masses of land. |
A narrow strip of land that connects two larger bodies of land and has water on both sides.
isthmus
narrow strip of land connecting two large land areas otherwise separated by the sea. Unquestionably the two most famous are the Isthmus of Panama, connecting North and South America, and the Isthmus of Suez, connecting Africa and Asia. Historically the Isthmus of Corinth was of major importance because it connected what otherwise would be the island of the Peloponnese with the rest of the Greek peninsula. Isthmuses are of great importance in plant and animal geography because they offer a path for the migration of land plants and animals between the two land masses they connect.
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