Earlier religious house, incomplete (5)
I believe the answer is:
prior
'earlier' is the definition.
('prior' can be a synonym of 'earlier')
'religious house incomplete' is the wordplay.
'religious house' becomes 'priory' (I've seen this before).
'incomplete' means to remove the last letter.
'priory' with its final letter taken away is 'PRIOR'.
(Other definitions for prior that I've seen before include "Coming before N a superior" , "Coming before in time or importance" , "High ranking person in monastery" , "Former - chief of religious house" , "head of a religious community" .)