Sicilian volcano (4)
I believe the answer is:
etna
'sicilian volcano' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for etna that I've seen before include "Neat volcano overturned" , "Constant smoker" , "one blowing top?" , "Volcano in Sicily, quite neat" , "Volcano; reverse of stake" .)