Fortress (7)
'fortress' is the definition.
(citadel can mean a fortified city)
This is all the clue.
(Other definitions for citadel that I've seen before include "Urban fortress" , "Fortress -- dialect (anag)" , "Urban stronghold - dialect (anag)" , "Highly-secure building" , "Fortress (in or near city)" .)
'fortress' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for castle that I've seen before include "Fortified place on the chess board" , "the home of a Sassenach?" , "Big building" , "Move king to safety - stronghold" , "splendid house" .)
'fortress' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stronghold that I've seen before include "Fortress" , "Defence" , "Keep" , "castle" .)
'fortress' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for tower that I've seen before include "tugboat" , "Wrote (anag.)" , "Stand very high (over)" , "Tall building - loom (over)" , "Turret" .)