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stain; blot; flaw; disgrace
その事件は彼の経歴に汚点を残した。
The incident left a stain on his career.
一度の失敗が一生の汚点になりかねない。
A single failure could become a lifelong disgrace.
汚点のない清廉な政治家として知られる。
He is known as a politician of integrity without any blemish.