A course of inquiry that leads nowhere.
Used other than figuratively or idiomatically: see blind, alley. A street or passageway that leads nowhere.
An example or the act of disappointing: a circumstance in which a positive expectation is not achieved.
The feeling or state of being disappointed: a feeling of sadness or frustration when something is not as good as one hoped or expected, or when something bad unexpectedly happens.
Something or someone that disappoints: that which causes disappointment.