bastion

Etymology

First attested in 1562. From French bastion, from Old French bastille (“fortress”).

noun

1. (architecture) A projecting part of a rampart or other fortification.
2. A well-fortified position; a stronghold or citadel.
3. (figurative) A person, group, or thing, that strongly defends some principle.
   a bastion of hope
   the bastion of democracy
4. Any large prominence; something that resembles a bastion in size and form.

verb

1. (transitive) To furnish with a bastion.