Green priest upset attorney over National Trust (7)
I believe the answer is:
verdant
'green' is the definition.
(thesaurus)
'priest upset attorney over national trust' is the wordplay.
'priest' becomes 'rev' (**).
'upset' shows that the letters should be reversed in order.
'attorney' becomes 'da' (District Attorney).
'over' says to put letters next to each other.
'national trust' becomes 'nt'.
'rev' written backwards gives 'ver'.
'ver'+'da'+'nt'='VERDANT'
(Other definitions for verdant that I've seen before include "Covered with lush green grass or vegetation" , "Leafy" , "Rather green" , "Having green growth" , "Green like grass or fields" .)