He's a pathological liar.

他是个说谎成性者。

《柯林斯英汉双解大词典》

Identified only as Paul, the newspaper claimed he was a 'pathological liar.

这名男子的真名是保罗，报纸上称他是一个“病态撒谎者”。

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"Cancer's life is a recapitulation of the body's life, its existence a pathological mirror of our own," Mukherjee writes.

慕克吉写道：“癌症的生长要了身体的命，它的存在就是我们自身的病理学镜子。”

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The problem with--there's a problem with gambling behavior because in a certain fraction of the population we have pathological gambling.

赌博行为有个特殊情况,在人群中总会有一小撮人,我们称之为病态赌博

耶鲁公开课 - 金融市场课程节选

Sequelae is a pathological condition resulting from a previous disease or injury.

BBC: Doctors warn over homeopathic 'vaccines'

Reams of research point to the same finding: physicians looking at the same thing will disagree with each other, or even with themselves, from 10 percent to 50 percent of the time during virtually every aspect of the medical-care process from taking a medical history to doing a physical examination, reading a laboratory test, performing a pathological diagnosis and recommending a treatment.

FORBES: Are Medical Treatments Keeping Up With Science?

McNamee called Clemens a "pathological liar" in a story published Sunday in the Daily News.

WSJ: Roger Clemens still dogged by NY steroids case