Alien doesn't apply for place in Sicily (4)
I believe the answer is:
etna
'in sicily' is the definition.
('Etna' is part of 'sicily')
'alien doesn't apply' is the wordplay.
'alien' becomes 'et' (extraterrestrial).
'doesn't apply' becomes 'NA' (abbreviation for not applicable).
'et'+'na'='ETNA'
'for place' is the link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for etna that I've seen before include "It can be scorching" , "Sicily's 15" , "Neat volcano overturned" , "feature spewing lava" , "Impressive mount" .)