Minister: a politician getting makeover (6)
I believe the answer is:
revamp
'makeover' is the definition.
(a revamp is a makeover or refurbishment)
'minister a politician getting' is the wordplay.
'minister' becomes 'rev' (short for reverend).
'politician' becomes 'MP' (Member of Parliament).
'getting' means one lot of letters go next to another.
'rev'+'a'+'mp'='REVAMP'
(Other definitions for revamp that I've seen before include "face-lift" , "Give makeover to" , "Make new, improve or up-date" , "new arrangement" , "overhaul" .)