Aloof, I’d upset street worker (7)
I believe the answer is:
distant
'aloof' is the definition.
(I've seen this before)
'i'd upset street worker' is the wordplay.
'upset' says the letters should be written backwards.
'street' becomes 'st'.
'worker' becomes 'ant' (worker is a type of ant).
'id' reversed gives 'di'.
'di'+'st'+'ant'='DISTANT'
(Other definitions for distant that I've seen before include "Remote in time or place" , "Aloof" , "Reserved - a long way off" , "Unfriendly; far off" , "Far apart in space or time" .)