Rats disturbed celebrity (4)
I believe the answer is:
star
'celebrity' is the definition.
(I've seen this in another clue)
'rats disturbed' is the wordplay.
'disturbed' indicates anagramming the letters.
'rats' anagrammed gives 'STAR'.
(Other definitions for star that I've seen before include "Public figure" , "See 21" , "Polaris, possibly" , "A heavenly body or film favourite" , "Lead actor" .)