acropolis (n.) Look up acropolis at Dictionary.com
"elevated part of a Greek city," often the site of original settlement and usually a citadel, 1660s, from Latinized form of Greek akropolis "citadel" (especially, with capital A-, that of Athens), from akros "highest, upper" (see acro-) + polis "city" (see polis). The plural would be acropoles.