Arthurian isle (6)
I believe the answer is:
avalon
'arthurian isle' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for avalon that I've seen before include "Place where King Arthur was brought after death" , "Where King Arthur was conveyed after death" , "Island paradise of Arthurian legend" , "Fabled Arthurian isle" , "Where King Arthur's body was brought" .)