A papal order to cause dismay (5)
I believe the answer is:
appal
'dismay' is the definition.
(I know that dismay can be written as appal)
'a papal order' is the wordplay.
'order' is an anagram indicator.
'papal' with letters rearranged gives 'APPAL'.
'to cause' is the link.
(Other definitions for appal that I've seen before include "Outrage" , "Greatly dismay" , "Put at rest (suspicion)" , "Dismay, horrify" , "Shock, horrify" .)