street smart vs smart

street smart is not a noun while smart is a noun.

Word	Noun	Adjective	Verb	Adverb
street smart	No	Yes	No	No
smart	Yes	Yes	Yes	No

street smart (noun)	smart (noun)
	a kind of pain such as that caused by a wound or a burn or a sore

street smart (adjective)	smart (adjective)
having the shrewd resourcefulness needed to survive in an urban environment	showing mental alertness and calculation and resourcefulness
	capable of independent and apparently intelligent action
	quick and brisk
	improperly forward or bold
	characterized by quickness and ease in learning
	painfully severe
	elegant and stylish

street smart (verb)	smart (verb)
	be the source of pain