Isth"mus . [L. isthmus, Gr. 'isqmo`s a neck, a neck of land between two seas, an isthmus, especially the Isthmus of Corinth; prob. from the root of 'ie`nai to go; cf. Icel. ei&edh; isthmus. See Issue.] Geog.
A neck or narrow slip of land by which two continents are connected, or by which a peninsula is united to the mainland; as, the Isthmus of Panama; the Isthmus of Suez, etc.
Isthmus of the fauces. Anat. See Fauces.
© Webster 1913.