I checked this hasn't been already suggested.bas·tion (bschn, -t-n)
n.
1. A projecting part of a fortification.
2. A well-fortified position.
3. One that is considered similar to a defensive stronghold: You are a bastion of strength. See Synonyms at bulwark.
[French, from Old French bastillon, from bastille, fortress; see bastille.]
bastioned adj.
Noun 1. bastion - a group that defends a principle; "a bastion against corruption"; "the last bastion of communism"
defence force, defense force, defence, defense - an organization of defenders that provides resistance against attack; "he joined the defense against invasion"
2. bastion - a stronghold into which people could go for shelter during a battle
citadel
acropolis - the citadel in ancient Greek towns
kremlin - citadel of a Russian town
Kremlin - citadel of Moscow, housing the offices of the Russian government
stronghold, fastness - a strongly fortified defensive structure
3. bastion - projecting part of a rampart or other fortification
fortification, munition - defensive structure consisting of walls or mounds built around a stronghold to strengthen it
from freedictionary.com
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