Wager heads turned in chapel (8)
I believe the answer is:
bethesda
'chapel' is the definition.
(I've seen this before)
'wager heads turned in' is the wordplay.
'wager' becomes 'bet' ('bet' can be a synonym of 'wager'**).
'turned' is an anagram indicator.
'in' is an insertion indicator.
'heads' with letters rearranged gives 'hesda'.
'bet' put within 'hesda' is 'BETHESDA'.
(Other definitions for bethesda that I've seen before include "church" , "Chapel" , "Healing pool (Jerusalem)" .)