A nasty boil removed, got rid of (9)
I believe the answer is:
abolished
'got rid of' is the definition.
('abolish' can be a synonym of 'get rid of')
'a nasty boil removed' is the wordplay.
'nasty' indicates anagramming the letters (a nasty or wrong spelling).
'removed' becomes 'shed' (shedding is a kind of removing).
'boil' anagrammed gives 'boli'.
'a'+'boli'+'shed'='ABOLISHED'
(Other definitions for abolished that I've seen before include "Got rid of" , "Done away with" .)