ancient city-state in the NE Peloponnesus: it dominated the Peloponnesus from the 7th cent. until the rise of Sparta
See Argos in American Heritage Dictionary 4
A city of ancient Greece in the northeast Peloponnesus near the head of the Gulf of Argolis. Inhabited from the early Bronze Age, it was one of the most powerful cities of ancient Greece until the rise of Sparta.