| castle(noun, keep, defense, refuge, fortification) |
| fortress(noun, hold, cover, keep, position) |
| citadel(noun, stronghold, keep, defense, fortification) |
| bulwark(noun, support, cover, position, guard) |
| stronghold(noun, hold, cover, keep, position) |
| fastness(noun, hold, cover, keep, position) |
| blockhouse(noun, defense, stronghold) |
| garrison(noun, cover, position, guard, shield) |
| redoubt(noun, support, cover, position, top) |
| defense(noun, support, cover, guard, resistance) |
| palisade(noun, cover, position, guard, shield) |
| dike(noun, cover, position, guard, shield) |
| fortification(noun, support, hold, cover, keep) |
| hold(noun, keep, defense, stronghold, seat) |
| stockade(noun, cover, position, guard, shield) |
| bastion(noun, support, cover, position, guard) |
| donjon(noun, hold, keep, defense, stronghold) |
| military post(noun, expression, idiom, station, quarters) |
| tower(noun, hold, part, keep, top) |
| trench(noun, cover, position, guard, shield) |