The definition of an isthmus is a narrow strip of land that connects two larger bodies of land and is surrounded by water on two sides.(noun)
An example of an isthmus is a land bridge.
See isthmus in Webster's New World College Dictionary
Origin: L < Gr isthmos, a neck, narrow passage, isthmus
See isthmus in American Heritage Dictionary 4
noun pl. isth·mus·es or isth·mi (-mīˌ)
Origin: , from Greek isthmos.
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