Wise man admits relic damaged in desecration (9)
I believe the answer is:
sacrilege
'desecration' is the definition.
(I know that desecration can be written as sacrilege)
'wise man admits relic damaged' is the wordplay.
'wise man' becomes 'sage' (sage is a kind of wise man).
'admits' indicates putting letters inside.
'damaged' indicates anagramming the letters.
'relic' anagrammed gives 'crile'.
'sage' enclosing 'crile' is 'SACRILEGE'.
'in' acts as a link.
(Other definitions for sacrilege that I've seen before include "Religious violation" , "Disrespect or damage to something sacred" , "Extreme disrespect for something holy" , "Violation of something sacred" , "Blasphemy" .)