1.NounThe 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.
"Even a trip to beautiful California can cause disappointment."
2.NounAn example or the act of disappointing: a circumstance in which a positive expectation is not achieved.
"The disappointment with our trip to California caused bickering."
3.NounSomething or someone that disappoints: that which causes disappointment.
"Even a trip to beautiful California can be a disappointment.; What a disappointment!"