What does «ístmico» mean in Spanish?

Relating to the isthmus.

Examples of use in Spanish: "el país ístmico" (hablando de Panamá).

"lenguas ístmicas".

"Convención del Canal Ístmico de 1903" (del canal de Panamá).

"se produjo un movimiento telúrico con 81 muertos en la franja ístmica".
(juegos ístmicos) Games in honor of Poseidon were held in the isthmus of Corinth.
(lenguas ístmicas) The most spoken branch of the Chibcha languages, which are spoken in Central America and Northeastern Colombia.