Church in a new series (5)
I believe the answer is:
chain
'series' is the definition.
(I know that chain is a type of series)
'church in a new' is the wordplay.
'church' becomes 'ch' (common abbreviation).
'new' is an anagram indicator.
'in'+'a'='ina'
'ina' is an anagram of 'ain'.
'ch'+'ain'='CHAIN'
(Other definitions for chain that I've seen before include "a number of hotels" , "Mountain range" , "Wickets so far apart in cricket" , "Succession" , "Event series" .)