1) Dead end 2) Dead-end street 3) Foundation universe 4) Fruitless course 5) Fruitless undertaking 6) Impasse 7) It has only one way in 8) It leads nowhere 9) Road to nowhere 10) Search-stymieing spot 11) Short story by Isaac Asimov 12) Unproductive path 
`Blind Alley` is a science fiction short story by Isaac Asimov. It was first published in the March 1945 issue of Astounding Science Fiction, and later included in the collection The Early Asimov (1972). Although the story postulates a race of intelligent non-humans, it is set in the Foundation universe, during the era of Trantor`s Galactic Emp......
[n] - a street with only one way in or out
cul de sac noun a street with only one way in or out
a road, alley, etc., that is open at only one end. · a position or situation offering no hope of progress or improvement: That line of reasoning will only lead you up another blind alley.