A street apart (4)
I believe the answer is:
away
'apart' is the definition.
(thesaurus)
'a street' is the wordplay.
'street' becomes 'way' (I've seen this before).
'a'+'way'='AWAY'
(Other definitions for away that I've seen before include "Distant or having left" , "'''... in a manger, no crib for a bed'' (carol) (4)'" , "Game played at opponents' ground" , "and 9: Christmas carol" , "Out of town" .)