Copper, mildly indecent, in church office (6)
I believe the answer is:
curacy
'church office' is the definition.
(I've seen this before)
'copper mildly indecent' is the wordplay.
'copper mildly' becomes 'cu' (Cu is the chemical symbol for copper. I am not sure about the 'mildly' bit.).
'indecent' becomes 'racy' (I've seen this in other clues).
'cu'+'racy'='CURACY'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for curacy that I've seen before include "ministerial office" , "post for clergyman" , "Church office" , "position for clergyman" , "Position occupied by junior priest in parish" .)