1. a group that defends a principle

- a bastion against corruption

- the last bastion of communism

Definition categories: group, defence, defense

2. a stronghold into which people could go for shelter during a battle

Similar word(s): citadel

Definition categories: man–made, fastness, stronghold

3. projecting part of a rampart or other fortification

Definition categories: man–made, fortification, munition