c. 1600, from Latin isthmius, from Greek isthmios "pertaining to the isthmus (of Corinth)," from isthmos (see isthmus). Originally in reference to the Isthmian Games, held at Corinth in honor of Poseidon.
Entries linking to isthmian
isthmus n.
1550s, from Latin isthmus, from Greek isthmos "narrow passage, narrow neck of land between two seas," originally especially that of Corinth, a word of unknown origin. Perhaps from eimi "to go" + suffix -thmo (compare ithma "a step, movement").