Treasury’s beginning cutting? More likely doing this (6)
I believe the answer is:
taxing
'likely doing this' is the definition.
The definition suggests a singular noun but the answer is not.
'treasury's beginning cutting? more' is the wordplay.
'treasury's beginning' becomes 't' (I can't justify this - if you can you should believe this answer much more).
'cutting?' becomes 'axing' (I've seen this in another clue).
'more' is a charade indicator (letters next to each other) (some letters added to the previous ones).
't'+'axing'='TAXING'
Can you help me to learn more?
(Other definitions for taxing that I've seen before include "'Not easily borne, very wearing (6)'" , "Burdensome" , "Making heavy demands, like Revenue Commissioners" , "Onerous" , "Physically or mentally demanding" .)