Bishop's Stortford originally involved in great work round China (9)
I believe the answer is:
episcopal
'bishop's' is the definition.
(I know this)
'stortford originally involved in great work round china' is the wordplay.
'originally' suggests taking the first letters.
'involved in' is an insertion indicator.
'great work' becomes 'epic' (I've seen this before).
'round china' becomes 'opal' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The initial letter of 'stortford' is 's'.
's' going within 'epic' is 'episc'.
'episc'+'opal'='EPISCOPAL'
Can you help me to learn more?
(Other definitions for episcopal that I've seen before include "Scottish Church" , "run by bishops" , "Governed by bishops" , "sees can be described thus" , "Relating to bishops" .)