Kind of bank that's making a profit (8)
I believe the answer is:
clearing
'a profit' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'kind of bank that's making' is the wordplay.
'kind' becomes 'cl' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'of bank' means to remove the middle letters (I've seen 'banks of' mean this (the banks are the sides of the word)).
'that's making' becomes 'earning' ('earn' can be a synonym of 'make').
'earning' with its middle removed is 'earing'.
'cl'+'earing'='CLEARING'
Can you help me to learn more?
(Other definitions for clearing that I've seen before include "Tract of land with no trees in a wooded area" , "Break in a forest" , "open area" , "Glade; declaring innocent" , "Weather improving" .)