Maybe Avalon features in this legend (4)
I believe the answer is:
isle
'maybe avalon features in this legend' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'in this legend' is the wordplay.
'in' indicates the answer is hidden within the clue.
'ISLE' can be found hidden inside 'this legend'.
Can you help me to learn more?
(Other definitions for isle that I've seen before include "Small bit of land surrounded by water" , "eg Man, Ely" , "one ringed in the main?" , "Small mass of land in the sea" , "eg Hoy, Yell or Sark" .)