Citadel

n.

1.

A fortress in or near a fortified city, commanding the city and fortifications, and intended as a final point of defense. Syn Stronghold. See Fortress.

Noun

1.

citadel - a stronghold into which people could go for shelter during a battle Synonyms: bastion

acropolis, bastion, beachhead, blockhouse, bridgehead, bunker, castle, donjon, fasthold, fastness, fort, fortress, garrison, garrison house, hold, keep, martello, martello tower, mote, motte, peel, peel tower, pillbox, post, rath, redoubt, safehold, strong point, stronghold, tower, tower of strength, ward