Nun coming down to new church in carriage (8)
I believe the answer is:
clarence
'carriage' is the definition.
(I know that Clarence is a type of carriage)
'nun coming down to new church' is the wordplay.
'nun coming' becomes 'clare' (I can't explain this - if you can you should believe this answer much more).
'down to' means one lot of letters go next to another (joining in a down clue).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'church' becomes 'CE' (Church of England).
'clare'+'n'+'ce'='CLARENCE'
'in' is the link.
Can you help me to learn more?
(Other definitions for clarence that I've seen before include "boy" , "Horse-drawn carriage; man's name" , "Duke drowned in a butt of Malmsey" , "He was supposedly drowned in malmsey" .)