Bath church's room (5)
I believe the answer is:
space
'room' is the definition.
(I know that room can be written as space)
'bath church's' is the wordplay.
'bath' becomes 'spa' (I've seen this in another clue).
'church' becomes 'CE' (abbreviation for Church of England).
'spa'+'ce'='SPACE'
(Other definitions for space that I've seen before include "Room; gap" , "Emptiness" , "A particular area for paces" , "Gap between words" , "Gap; --- Oddity (Bowie)" .)