Comic coming back round with letter (8)
I believe the answer is:
landlord
'letter' is the definition.
(I've seen this before)
'comic coming back round with' is the wordplay.
'comic' becomes 'droll' (I've seen this before).
'coming back' shows that the letters should be reversed in order.
'round' means one lot of letters goes inside another.
'with' becomes 'and'.
'droll' reversed gives 'llord'.
'llord' enclosing 'and' is 'LANDLORD'.
(Other definitions for landlord that I've seen before include "Pub manager" , "Male lessor" , "Mein host" , "Property letter" , "Publican" .)