Outstanding foreigner in the street (7)
I believe the answer is:
salient
'outstanding' is the definition.
('salient' can be a synonym of 'outstanding')
'foreigner in the street' is the wordplay.
'foreigner' becomes 'alien' ('alien' can be a synonym of 'foreigner').
'in the' is an insertion indicator.
'street' becomes 'st'.
'alien' put inside 'st' is 'SALIENT'.
(Other definitions for salient that I've seen before include "defence work" , "Noteworthy" , "Leaping (heraldry)" , "Prominent, striking" , "Entails being most noticeable" .)