fortress Definition

fort, citadel, castle, fortified, stronghold, bastion, bulwark, bunker, heartland, security, house, resilience, fortitude, strength, useless, strong, certainty, hard, fortaleza, tycoon, monroe, robustness, very, firmness, high, loud, battery, highly, louisbourg, rampart, redoubt, palace, outpost, garrison, edifice, moat, blockhouse, stockade, martello tower, dungeon, triumphal arch, antonine wall, cathedral, medieval, fortalice, gatehouse, monastery, fortresses, defensive structure, barmkin, crownwork, fortifications, propugnacle, castellate, castellation, hornwork, fortification, guerite, kremlin, afforcement, battlements, tower of london, caponier, refortification, castlery, palisade, acropolis, impregnability, colosseum, maginot line, lair, contravallation, warren, monolith, counterguard, ctesiphon, teutonic order, fortlet, castlet, turrets, embattail, terreplein, gun emplacement, eyrie, ziggurat, barbarians, hilltop, porticoes, motte, casern, bridgehead, watchtower, tenaille, vauntmure, demesne, megaliths, crenellations, besiegers, manor house, enclave,