European combined with Northern Ireland in backing thread promoting unity (10)
I believe the answer is:
ecumenical
'thread promoting unity' is the definition.
I can't tell whether this defines the answer.
'european combined with northern ireland in backing' is the wordplay.
'european' becomes 'e' (abbreviation e.g. EU).
'combined with' becomes 'cum' (I've seen this before).
'northern ireland' becomes 'ni'.
'in' means one lot of letters goes inside another.
'backing' becomes 'ecal' (I am not sure about this - if you are sure you should believe this answer much more).
'ni' placed within 'ecal' is 'enical'.
'e'+'cum'+'enical'='ECUMENICAL'
Can you help me to learn more?
(Other definitions for ecumenical that I've seen before include "Promoting unity between churches" , "seeking to promote unity" , "trying to promote unity" , "of the church" .)