Spray over top of neglected church building (7)
I believe the answer is:
minster
'church building' is the definition.
(minster is a kind of church building)
'spray over top of neglected' is the wordplay.
'spray' becomes 'mister' (spray device).
'over' means one lot of letters goes inside another.
'top of' suggests taking the first letters.
The first letter of 'neglected' is 'n'.
'mister' enclosing 'n' is 'MINSTER'.
(Other definitions for minster that I've seen before include "Large church (or cathedral at York)" , "Large church (eg, York)" , "Old monastic cathedral, such as York's" , "Clergyman" , "Large important church" .)