Gaol rebuilt houses barbarian in Calvary (8)
I believe the answer is:
golgotha
'calvary' is the definition.
(synonyms)
'gaol rebuilt houses barbarian' is the wordplay.
'rebuilt' indicates an anagram.
'houses' indicates putting letters inside.
'barbarian' becomes 'goth' (synonyms).
'gaol' with letters rearranged gives 'gola'.
'gola' going around 'goth' is 'GOLGOTHA'.
'in' is the link.
(Other definitions for golgotha that I've seen before include "Aramaic name of Calvary" , "The Aramaic Way of the Cross" , "Place of Crucifixion" , "Hill of the crucifixion" , "Hill where Jesus was crucified" .)