Really not on being deprived (5,3)
I believe the answer is:
badly-off
'being deprived' is the definition.
(thesaurus)
'really not on' is the wordplay.
'really' becomes 'badly' (I can't explain this - if you can you should believe this answer much more).
'not on' becomes 'off' ('off' is the opposite to 'on').
'badly'+'off'='BADLY-OFF'
Can you help me to learn more?
(Other definitions for badly-off that I've seen before include "Poorly financed" , "Poor" , "At a disadvantage" , "In dire straits financially" , "Hard up" .)