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matter causing distress; something causing worry
妹は姉に悩み事を打ち明けた。
My younger sister confided her worries to our older sister.
社長は会社の経営の悩み事が尽きない。
The company president has endless worries about the business's management.
彼は友人たちに自分の悩み事を打ち明けられずにいた。
He couldn't bring himself to confide his worries to his friends.