Stranger aversion (10)
I believe the answer is:
xenophobia
I believe this clue is a double definition.
'stranger' is the first definition.
(thesaurus)
'aversion' is the second definition.
(thesaurus)
(Other definitions for xenophobia that I've seen before include "hating aliens" , "Hatred of the foreign" , "Excessive fear of foreigners" , "for blocking of foreign connections?" , "Fear or dislike of foreigners" .)