Fab Four drummer (5)
I believe the answer is:
ringo
'fab four drummer' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ringo that I've seen before include "Beatle Starr" , "Starr drummer" , "Beatles drummer" , "The drumming Beatle" , "John Paul I (and another) backed" .)