City codebreaker briefly identified (5)
I believe the answer is:
turin
'city' is the definition.
(Turin is an example)
'codebreaker briefly identified' is the wordplay.
'codebreaker' becomes 'Turing' (WW2 codebreaker Alan Turing).
'briefly identified' means to remove the last letter (a briefer form of the word).
'turing' with its final letter taken away is 'TURIN'.
(Other definitions for turin that I've seen before include "It. city housing shroud" , "14 Italian city" , "foreign city" , "City of northwest Italy (with a shroud)" , "First capital in 1861 of united Italy" .)