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to be disheartened; to be dejected; to be discouraged; to be disappointed
suddenly (losing a lot of weight); looking emaciated; becoming very thin
仕事のストレスでげっそりした顔になった。
My face became haggard from work stress.
病気でげっそりと痩せてしまって心配だ。
I'm worried because I got haggardly thin from illness.
入院中にげっそり痩せた彼の顔を見て言葉を失った。
I was at a loss for words when I saw how gaunt he had become during his hospitalization.