Getting on with a good editor (4)
I believe the answer is:
aged
'getting on' is the definition.
(thesaurus)
'with a good editor' is the wordplay.
'with' says to put letters next to each other.
'a good' becomes 'ag' (I've seen this in other clues**).
'editor' becomes 'ed'.
'ag' put next to 'ed' is 'AGED'.
(Other definitions for aged that I've seen before include "Grew old" , "Geriatric" , "Old or ancient" , "Getting on" , "way over the hill" .)