Give a new name to (7)
I believe the answer is:
retitle
'give a new name to' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for retitle that I've seen before include "Name afresh" , "Give a new name to" , "Give a different name to (a book)" , "name differently" , "Call again on" .)