Give Adele a seat in said fortress (7)

I believe the answer is:

citadel

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'fortress' is the definition.
(citadel can mean a fortified city)

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for citadel that I've seen before include "Kremlin" , "Keep - castle" , "Stronghold into which people could go for shelter during a battle" , "Stronghold usually within the walls" , "place of refuge" .)

I've seen this clue in the Sydney Morning Herald.

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