Expurgate (6)
I believe the answer is:
censor
'expurgate' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for censor that I've seen before include "Official with power to prohibit distribution of material" , "use blue pencil" , "Person authorised to remove unacceptable passages" , "Bowdlerise" , "Roman magistrate" .)