Weak or vulnerable point; fault, esp in sbs character, which can lead to his downfall.

致命弱点；（尤指某人个性中可导致一败涂地的）缺陷。

youdao

After a double fault on the first point, Li's forehand gave Azarenka the early lead.

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For those who sincerely hold such a belief, and who apply their offense and outrage equally against all offending parties, I find no fault and fully understand their point of view.

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"We just don't have enough information at this point to either assess blame, innocence or fault, " Kimmitt said.

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