Church and state introducing more organised ritual (8)
I believe the answer is:
ceremony
'ritual' is the definition.
(I've seen this before)
'church and state introducing more organised' is the wordplay.
'church' becomes 'ce' (Church of England).
'and' is a charade indicator (letters next to each other).
'state' becomes 'ny' (abbreviation for New York the US state).
'introducing' means one lot of letters goes inside another (some letters introduced or inserted into others).
'organised' is an anagram indicator.
'ce'+'ny'='ceny'
'more' anagrammed gives 'remo'.
'ceny' placed around 'remo' is 'CEREMONY'.
(Other definitions for ceremony that I've seen before include "Rite or formal act for special occasion" , "Religious rite" , "Formal event performed on a special occasion" , "Activity on a solemn occasion" , "Rite, ritual or formal act" .)