Inclination to be corrupt (4)
I believe the answer is:
bent
This clue is a double definition.
'inclination' is the first definition.
(I know that bent is a type of inclination)
'be corrupt' is the second definition.
(I've seen this before)
'to' acts as a link.
(Other definitions for bent that I've seen before include "Crooked - penchant" , "Crooked - inclination" , "Natural aptitude" , "Angled; corrupt" , "Dishonest - inclination" .)