See discontent in Webster's New World Roget's A-Z Thesaurus II
noun
Unhappiness caused by the failure of one's hopes, desires, or expectations:
disappointment, discontentment, disgruntlement, dissatisfaction, letdown, regret. See happy
verb
To cause unhappiness by failing to satisfy the hopes, desires, or expectations of:
disappoint, disgruntle, dissatisfy, let down. See happy
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