fail to be or do sth as good, interesting etc as was hoped for or desired or expected by (sb) 使（某人）失望: The tenor disappointed us by singing flat. 那位男高音歌手调门儿唱得很低, 十分扫兴. * I can't disappoint my public by retiring. 我可不能退休, 否则大家会失望的. * Don't disappoint me by being late again. 别再迟到了, 不要叫我失望. * I've often been disappointed in love, ie not been loved in return by sb I have loved. 我经常情场失意. 
prevent (hope, plan, etc) from becoming reality 使（希望﹑ 计划等）不能实现: disappoint sb's expectations, sb's calculations, etc 使某人的希望破灭﹑ 使某人的如意算盘落空. > disappointed adj ~ (about/at sth); ~ (in/with sb/sth); ~ (to do sth/that...) sad or dissatisfied because sb has failed, some desired event has not happened, etc 失望的; 失意的; 受挫的: be disappointed about/at sb's failure 对某人的失败感到失望 * I was disappointed with his performance. 他的表现令我失望. * I'm disappointed in you: I expected you to win. 你让我失望了, 我本来指望你能赢的. * He was disappointed to hear they were not coming. 他听说他们不来了, 感到很扫兴. * I was disappointed not to be chosen. 我没被挑中, 感到很沮丧. disappointedly adv.
disappointing adj causing sb to be disappointed 令人失望的; 扫兴的: a disappointing novel 令人失望的小说 * The weather this summer has been disappointing. 今年夏天的天气一直使人不痛快. disappointingly adv: Disappointingly, he had nothing new to show us. 他没什麽新鲜东西给我们看, 使人感到失望.