Churchwoman's long passage (7)
I believe the answer is:
channel
'passage' is the definition.
(I know that channel is a type of passage)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for channel that I've seen before include "Navigable part of a waterway" , "Water passage; TV station" , "Length of water between two land masses" , "vehicle" , "Seaway south of England" .)