Active volcano in Sicily (4)
I believe the answer is:
etna
'active volcano in sicily' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for etna that I've seen before include "It could erupt" , "Sicilian volcano" , "From a dangerous height" , "A feature of Sicily" , "it may produce steam and ash" .)