Clergyman in vicious circle (6)
I believe the answer is:
cleric
'clergyman' is the definition.
(cleric is a kind of clergyman)
'vicious circle' is the wordplay.
'vicious' indicates an anagram.
'circle' anagrammed gives 'CLERIC'.
'in' is the link.
(Other definitions for cleric that I've seen before include "Eg, priest" , "Religious official" , "Man of the cloth" , "Priest caught in circle" , "Church minister" .)