(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"
having existence or being or actuality; "an attempt to refine the existent machinery to make it more efficient"; "much of the beluga caviar existing in the world is found in the Soviet Union and Iran"