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experiencing or marked by or causing sadness or sorrow or discontent; "unhappy over her departure"; "unhappy with her raise"; "after the argument they lapsed into an unhappy silence"; "had an unhappy time at school"; "the unhappy (or sad) news"; "he looks so sad"
disappointingly unsuccessful; "disappointed expectations and thwarted ambitions"; "their foiled attempt to capture Calais"; "many frustrated poets end as pipe-smoking teachers"; "his best efforts were thwarted"