Fleet inspector retires following censure (5)
I believe the answer is:
rapid
'fleet' is the definition.
(I've seen this before)
'inspector retires following censure' is the wordplay.
'inspector' becomes 'di' (I've seen this in other clues).
'retires' says the letters should be written backwards.
'following' is a charade indicator (letters next to each other).
'censure' becomes 'rap' (I've seen this before).
'di' back-to-front is 'id'.
'id' put after 'rap' is 'RAPID'.
(Other definitions for rapid that I've seen before include "Swift, speedy" , "haste" , "Speedy (5)" , "Quickly accomplished" , "Moving at speed" .)