Banks long-term capital gain for Big Cat (4)
I believe the answer is:
lion
'for big cat' is the definition.
(lion is a kind of big cat)
'banks long-term capital gain' is the wordplay.
I cannot quite understand how this works, but
'long' could be 'l' and 'l' is found in the answer.
The remaining letters 'ion' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for lion that I've seen before include "Buddhist scripture; Sanskrit rule" , "Cat, the king of the beasts" , "Wild cat" , "Big cat with pride" , "Courageous person" .)