Dutiful editor in charge, old-fashioned on the outside (9)
I believe the answer is:
dedicated
'dutiful' is the definition.
Both the answer and definition are adjectives. Perhaps you can see a link between them that I can't see?
'editor in charge old-fashioned on the outside' is the wordplay.
'editor' becomes 'ed' (abbreviation).
'in charge' becomes 'ic' (abbreviation for 'in charge').
'old fashioned' becomes 'dated' (I've seen this before).
'on the outside' indicates putting letters inside.
'ed'+'ic'='edic'
'edic' going into 'dated' is 'DEDICATED'.
Can you help me to learn more?
(Other definitions for dedicated that I've seen before include "Determined" , "Hard working" , "Committed" , "Consecrated - single-minded" , "exclusive" .)