He has a pound remaining - for pressing his suit? (5)
I believe the answer is:
lover
'he has a pound' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'remaining for pressing his suit?' is the wordplay.
'remaining' becomes 'over' (as in 'we ate them all but had one over').
'for' is a charade indicator (letters next to each other) (I've seen this in other clues).
'pressing his suit?' becomes 'l' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'over' put after 'l' is 'LOVER'.
Can you help me to learn more?
(Other definitions for lover that I've seen before include "One enjoys" , "Boyfriend" , "One of a couple" , "'Lady Chatterley's - - ' by D H Lawrence" , "Romantic partner" .)