Webster's Revised Unabridged Dictionary · 1913

Peloponnesian

Peloponnesian , adjective

[Latin Peloponnesius, from Peloponnesus, Greek {not transcribed}, lit., the Island of Pelops; {not transcribed}, {not transcribed}, Pelops + {not transcribed} an island.]

Of or pertaining to the Peloponnesus, or southern peninsula of Greece.
A native or an inhabitant of the Peloponnesus.