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single amount (of money); one-off payment; lump sum
bonus
退職時に一時金が支給された。
A lump sum was paid out on retirement.
事故の慰謝料として一時金が支払われた。
A lump sum was paid as compensation for the accident.
会社は業績改善の報奨として社員に一時金を出した。
The company gave employees a bonus as a reward for improved performance.