1.  blind alley(n = noun.artifact) cul de sac, dead-end street, impasse - a street with only one way in or out; Array
is a kind of thoroughfare

2.  blind alley(n = noun.act) Array - (figurative) a course of action that is unproductive and offers no hope of improvement; "all the clues led the police into blind alleys"; "so far every road that we've been down has turned out to be a blind alley"
is a kind of course, course of action

N  closure, occlusion, blockade, shutting up, obstruction, embolus, contraction, infarction, constipation, obstipation, blind alley, blind corner, keddah, cul-de-sac, caecum, imperforation, imperviousness, impermeability, stopper, closed, shut, operculated, unopened, unpierced, imporous, caecal, closable, imperforate, impervious, impermeable, impenetrable, impassable, unpassable, invious, pathless, wayless, untrodden, untrod, unventilated, air tight, water tight, hermetically sealed, tight, snug.

alley, alley cat, blind, blind bend, blind corner, blind curve, blind date, blind drunk, blind eel, blind faith, blind flying, blind gentian, blind gut, blind impulse, blind landing, blind man's buff, blind person, blind reader, blind side, blind snake, blind spot, blind staggers, blind stitching, blind to, blind trust, bowling alley, color blind, double blind, fly blind, roller blind, skittle alley, tin pan alley, turn a blind eye, venetian blind, western blind snake, window blind