Lucrative, as a contract (3)
I believe the answer is:
fat
'lucrative as a contract' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fat that I've seen before include "eg Lard" , "and 24: Overpaid City type" , "Corpulent; little (chance)" , "Profitable" , "Greasy substance" .)