Letdown

Noun

 * 1) Disappointment, the sad state of not living up to expectations.
 * It's such a letdown, I thought it was going to be better than this.

Thesaurus
abasement, abatement, allayment, alleviation, arrest, assuagement, bafflement, balk, betrayed hope, blasted expectation, blighted hope, blow, blunting, buffet, calming, check, comedown, cruel disappointment, damping, dash, dashed hope, deadening, debasement, deceleration, defeat, deflation, delay, demulsion, descent, detention, diminution, disappointment, discomfiture, disgrace, disillusionment, dissatisfaction, drag, dulcification, dulling, dump, ease-off, ease-up, easing, embarrassment, failure, fallen countenance, falling-off, fiasco, fizzle, flagging, foiling, forlorn hope, frustration, hangdog look, holdup, hope deferred, humbled pride, humiliation, hushing, lag, leniency, lessening, letup, lightening, loosening, lulling, minus acceleration, mirage, mitigation, modulation, mollification, mortification, obstruction, pacification, palliation, put-down, quietening, quieting, reduction, relaxation, remission, retardation, retardment, self-abasement, self-abnegation, self-diminishment, setback, setdown, shame, shamefacedness, shamefastness, slack-up, slackening, slowdown, slowing, slowing down, slowup, softening, soothing, sore disappointment, subduement, tantalization, tease, tempering, tranquilization

Alternative forms

 * let-down