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paying back a favour; repayment (of an obligation, kindness, etc.)
親に恩返しをしたい。
I want to repay my parents' kindness.
先生への恩返しの気持ちでいっぱいです。
I am filled with a desire to repay my teacher's kindness.
故郷に恩返しするため、彼は会社を設立した。
To repay his hometown, he established a company.