Volcanic expulsion swirling on legendary island (6)
I believe the answer is:
avalon
'legendary island' is the definition.
(I've seen this in another clue)
'volcanic expulsion swirling on' is the wordplay.
I cannot really understand how this works, but
'on' is present in the answer.
The remaining letters 'aval' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for avalon that I've seen before include "Where King Arthur's body was brought" , "Isle of Celtic myth" , "Island where King Arthur was buried" , "Place to which the body of King Arthur was taken" , "Celtic island of the blessed" .)