Cushion concerning chaplain (5)
I believe the answer is:
padre
'chaplain' is the definition.
(I know that chaplain can be written as padre)
'cushion concerning' is the wordplay.
'cushion' becomes 'pad' (to cushion something is to pad it).
'concerning' becomes 're' (both can mean on a particular topic).
'pad'+'re'='PADRE'
(Other definitions for padre that I've seen before include "Services' chaplain" , "Father" , "Minister" , "Military chaplain" , "Man of god - drape (anag)" .)