In a 95-minute speech in Fort Dodge, Iowa, on Thursday night, Donald Trump seemed obsessed with the word "pathological."

Ben Carson, Trump's rival in GOP presidential primary, has written that he felt "pathological anger" as a young man. Trump seized on the phrase to attack his rival. The term "pathological," Trump said, meant that Carson's anger could not be cured.

"He said he has pathological disease. Now if you're pathological, there's no cure for that, folks, okay? There's no cure for that," Trump said.

This, Trump suggested, made Carson unfit to hold high office.

"What the hell have we come to?" Trump asked. "We're going to put somebody in office who considers himself to have pathological disease. Read the definition in the dictionary of pathological disease."

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People frequently use words such as "insane," "crazy" and "pathological" in an informal way, without meaning anything scientific. Trump, though, made clear he was using the word in a pretty technical sense, lingering on the specific phrase "pathological disease," directing his audience to the dictionary, comparing the nature of Carson's anger to the pathology of a child molester. Doctors and psychologists, he said, can't cure that condition.

"If you're a child molester, there's no cure. They can't stop you," Trump said. "Pathological, there's no cure."

Yet, none of this is really true about what it means to be pathological. Let's start with Trump's own admonition to look at the dictionary.  Here is the definition of "pathological," according to Webster's New World Diction of American English, Third College Edition (1988):

pathological adj. 1 of pathology; of or concerned with disease 2 due to or involving disease 3 governed by a compulsion; compulsive [a pathological liar] Also pathologic

And "pathology," for those keeping score at home, refers to "the branch of medicine that deals with the nature of disease." None of these definitions say anything about a condition or trait being incurable. The word can refer to any disease or compulsion, whether or not there is a treatment or a cure.

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"The notion that a pathology is something that cannot be treated or cured doesn't make much sense," wrote John Hibbing, a professor of political science and psychology at the University of Nebraska, Lincoln, in an e-mail. "If the statement is true, why are there pathologists?"

Dr. William Carpenter, a psychiatrist at the University of Maryland, also said that Trump's definition was inaccurate.

"Of course not," he said when asked in an interview Friday whether the term "pathological" referred to conditions that could not be cured.

Carson's use of the phrase "pathological anger" in his book implied only that Carson had some kind of disease, Carpenter explained, not that his anger was permanent.

"All of us get angry," the psychiatrist said. "Pathologic anger would imply that there's a disease process that's causing it."

Even Trump's claim that pedophilia is a condition that can't be cured isn't entirely accurate, said psychologist Michael Seto. Trump seemed to suggest that even with treatment, people can neither control their desires or move beyond whatever emotional turmoil is causing them to harm others.

"Both for the anger problems, and for the sexual offending, that's not the case," said Seto, who is the director of forensic research at the Royal Ottawa Health Care Group. "Many of them do not go on to offend again, with appropriate intervention."