ἰσθμός

Etymology
A derivation from with a suffix -θμο- has been assumed, comparing also 🇨🇬. However, the -σ- is unexplained, so the word could well be of origin.

Noun

 * 1) neck, narrow passage of the body
 * 2)  pharynx, fauces
 * 3) neck of land between two seas; isthmus
 * 4) narrow ridge
 * 5) strait, narrow channel