B1unhappy because someone or something was not as good as you hoped or expected, or because something did not happen: We were deeply disappointed at/about the result.His parents were bitterly disappointed in/with him.[+ (that)]She was disappointed (that) they hadn't phoned.[+ to infinitive]He was disappointed to find they'd already gone.If you're expecting Dad to let you borrow his car, you're going to be sorely disappointed.Feeling sad and unhappydisappointedly