Mickey's companion, an alien (4)
I believe the answer is:
finn
This clue might be a double definition.
'mickey's companion' is the first definition.
The definition and answer can be both people as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'alien' is the second definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'an' acts as a link.
Can you help me to learn more?
(Other definitions for finn that I've seen before include "EU statesman" , "adventurer in Mark Twain story" , "hero of American fiction" , "National" , "Northern European" .)