acropolis

from WordNet (r) 3.0 (2006)

acropolis
    n 1: the citadel in ancient Greek towns

from The Collaborative International Dictionary of English v.0.48

Acropolis \A*crop"o*lis\, n. [Gr. 'akro`polis; 'a`kros extreme +
   po`lis city.]
   The upper part, or the citadel, of a Grecian city;
   especially, the citadel of Athens.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

31 Moby Thesaurus words for "acropolis":
      bastion, beachhead, blockhouse, bridgehead, bunker, castle,
      citadel, donjon, fasthold, fastness, fort, fortress, garrison,
      garrison house, hold, keep, martello, martello tower, mote, motte,
      peel, peel tower, pillbox, post, rath, safehold, strong point,
      stronghold, tower, tower of strength, ward

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