One who ill-treats is cheapskate going around America (7)
I believe the answer is:
misuser
'one who ill-treats' is the definition.
The definition suggests a singular noun which matches the answer.
'cheapskate going around america' is the wordplay.
'cheapskate' becomes 'miser' (I've seen this before).
'going around' is an insertion indicator.
'america' becomes 'us' (abbreviation for the United States).
'miser' going around 'us' is 'MISUSER'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for misuser that I've seen before include "bad employer" , "Someone cruel" , "One giving bad treatment" , "One guilty of malpractice" , "how wasteful he is" .)