Church with brownish-yellow room (7)
I believe the answer is:
chamber
'room' is the definition.
(chamber is a kind of room)
'church with brownish-yellow' is the wordplay.
'church' becomes 'ch' (common abbreviation).
'with' says to put letters next to each other.
'brownish yellow' becomes 'amber' (synonyms).
'ch'+'amber'='CHAMBER'
(Other definitions for chamber that I've seen before include "Room - part of a legislature" , "Official room" , "Enclosed cavity, part of gun" , "vault" , "Room where a judge transacts business" .)