Discover manager's back in bank (5)
I believe the answer is:
learn
'discover' is the definition.
(I know that discover can be written as learn)
'manager's back in bank' is the wordplay.
'back' says to take the final letters (the letter at the back).
'in' is an insertion indicator.
'bank' becomes 'lean' (bank can mean to lean or tilt).
The last letter of 'manager' is 'r'.
'r' put within 'lean' is 'LEARN'.
(Other definitions for learn that I've seen before include "Con" , "Study or digest" , "Take in" , "Read up on" , "Get to know" .)