Dislodge after a tune's rewritten (6)
I believe the answer is:
unseat
'dislodge' is the definition.
(I've seen this in another clue)
'after a tune's rewritten' is the wordplay.
'after' means one lot of letters go next to another.
'rewritten' indicates an anagram.
'a'+'tunes' is 'atunes'.
'atunes' anagrammed gives 'UNSEAT'.
(Other definitions for unseat that I've seen before include "Remove from power" , "Dislodge from saddle" , "Throw (as a 15?)" , "Get out of office" , "Cause to fall from the saddle" .)