Member of the clergy soon after beginning of chaplaincy (5)
I believe the answer is:
canon
'member of the clergy' is the definition.
(type of clergyman)
'soon after beginning of chaplaincy' is the wordplay.
'soon' becomes 'anon' (synonyms).
'after' is a charade indicator (letters next to each other).
'beginning of' indicates taking the first letters.
The initial letter of 'chaplaincy' is 'c'.
'anon' after 'c' is 'CANON'.
(Other definitions for canon that I've seen before include "Literary works of quality" , "Big type" , "Church decree or law" , "Senior clergyman" , "General principle or senior priest" .)