n.; pl.Isthmuses [ 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. eið 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. [ 1913 Webster ]
Isthmus of the fauces. (Anat.) See Fauces. [ 1913 Webster ]