Get rid of main changes in aristocracy (9)
I believe the answer is:
eliminate
'get rid' is the definition.
(I've seen this before)
'main changes in aristocracy' is the wordplay.
'changes' is an anagram indicator.
'in' indicates putting letters inside.
'aristocracy' becomes 'elite' (I've seen this before).
'main' is an anagram of 'mina'.
'mina' inserted within 'elite' is 'ELIMINATE'.
'of' is the link.
(Other definitions for eliminate that I've seen before include "Discard - exclude" , "Eradicate" , "Annihilate" , "Completely remove, get rid of" , "defeat" .)