blind alley vs dead-end street

blind alley and dead-end street both are nouns.

Word	Noun	Adjective	Verb	Adverb
blind alley	Yes	No	No	No
dead-end street	Yes	No	No	No

As nouns, blind alley and dead-end street are synonyms defined as:

Other synonyms of blind alley include cul de sac, impasse.

blind alley (noun)	dead-end street (noun)
(figurative) a course of action that is unproductive and offers no hope of improvement	a street with only one way in or out
a street with only one way in or out