Ritual worship where smaller branches worked together in discussion? (5)
I believe the answer is:
wicca
'ritual worship' is the definition.
(modern pagan religion)
'smaller branches worked together in discussion?' is the wordplay.
'smaller branches worked together' becomes 'wicker' (as in wicker baskets).
'in discussion?' indicates a 'sounds like' (homophone) clue (I've seen 'in discussion' mean this).
'wicker' is a homophone of 'WICCA'.
'where' acts as a link.
(Other definitions for wicca that I've seen before include "paganism" , "Cult of modern witchcraft" , "Practice of witchcraft" , "Magic" .)