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