Foreigner is primarily all right (5)
I believe the answer is:
alien
'foreigner' is the definition.
(synonyms)
'primarily all right' is the wordplay.
'primarily' says to take the initial letters.
'right' becomes 'lien' (I've seen this before).
The first letter of 'all' is 'a'.
'a'+'lien'='ALIEN'
'is' acts as a link.
(Other definitions for alien that I've seen before include "repugnant" , "movie!" , "Foreign (from outer space?)" , "24a [ESTRANGE]" , "Little green man, perhaps" .)