Synonyms of the word 
LETDOWN → DISAPPOINTMENT - DISSATISFACTION
letdown
- n. Alternative form of let-down.
disappointment
- n. (uncountable) The emotion felt when a strongly held expectation is not met.
- n. (countable) A circumstance in which a strongly held expectation is not met.
dissatisfaction
- n. unhappiness or discontent.
- n. the cause of such feelings.
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