Cabaret if rotten needs make up (9)
I believe the answer is:
fabricate
'make up' is the definition.
(I know that make up can be written as fabricate)
'cabaret if rotten' is the wordplay.
'rotten' is an anagram indicator.
'cabaret'+'if'='cabaretif'
'cabaretif' is an anagram of 'FABRICATE'.
'needs' is the link.
(Other definitions for fabricate that I've seen before include "Make up; manufacture" , "Tell lies" , "Construct or invent" , "forge" , "Invent, make up" .)