Excellent beef (5)
I believe the answer is:
bully
This clue is a double definition.
'excellent' is the first definition.
(I've seen this before)
'beef' is the second definition.
(bully beef is corned beef)
(Other definitions for bully that I've seen before include "Playground thug" , "Flashman, say" , "Browbeater" , "Intimidating person" , "Tinned beef" .)