Branch openings for leader in merchant banking (4)
I believe the answer is:
limb
'branch' is the definition.
(I know that branch can be written as limb)
'openings for leader in merchant banking' is the wordplay.
'openings for' says to take the initial letters (the letters which open the words).
The first letters of 'leader in merchant banking' is 'LIMB'.
(Other definitions for limb that I've seen before include "Large tree branch" , "arm, perhaps" , "Branch - arm - leg" , "Branch of a tree (risky to go out on)" , "Part of body or branch of tree" .)