Priest absorbed by Roman Catholic memorial (5)
I believe the answer is:
relic
'memorial' is the definition.
(I've seen this before)
'priest absorbed by roman catholic' is the wordplay.
'priest' becomes 'eli' (I've seen this before).
'absorbed by' indicates putting letters inside.
'roman catholic' becomes 'rc' ('r.c.' can be a synonym of 'roman catholic').
'eli' placed within 'rc' is 'RELIC'.
(Other definitions for relic that I've seen before include "for remembrance" , "Saint's body part?" , "Memorial of antiquity" , "Memento; souvenir" , "One may venerate this" .)