Clergyman playing charades endlessly – party! (10)
I believe the answer is:
archdeacon
'clergyman' is the definition.
(I know that archdeacon is a type of clergyman)
'playing charades endlessly party' is the wordplay.
'playing' is an anagram indicator.
'endlessly' means to remove the last letter.
'party' becomes 'con' (abbreviation for Conservative Party).
'charades' with its final letter taken away is 'charade'.
'charade' with letters rearranged gives 'archdea'.
'archdea'+'con'='ARCHDEACON'
(Other definitions for archdeacon that I've seen before include "Church dignitary" , "Church official" , "Member of clergy" , "Senior Christian cleric" , "ecclesiastical dignitary" .)