pathological

American  

[path-uh-loj-i-kuhl] / ˌpæθ əˈlɒdʒ ɪ kəl /

Also pathologic

adjective

1. 

   of or relating to pathology, or the science or study of diseases and their causes.

   Research into the pathological origins of alcoholism is ongoing.

2. caused by, indicative of, or involving disease.

   Her white blood cell count had fallen to a pathological level.

3. caused by or evidencing a mentally disturbed condition.

   He is a pathological hoarder.

   They show a pathological lack of concern for the suffering of others.

4. dealing with diseases.

   The neurologist kept a pathological casebook from her practice as a source of examples for lectures.

5. Mathematics. designating a phenomenon or object, such as a function, that is logically and correctly defined but has counterintuitive or paradoxical properties.

6. Computers. relating to or producing a failed outcome or one that is contrary to what was intended or expected.

   This is just an example of what happens when the algorithm encounters pathological data.

   A pathological input shouldn't break the algorithm.

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pathological British  

/ ˌpæθəˈlɒdʒɪkəl /

adjective

1. of or relating to pathology

2. relating to, involving, or caused by disease

3. informal compulsively motivated

   a pathological liar

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Other Word Forms

• nonpathologic
  adjective
• nonpathological
  adjective
• postpathologic
  adjective
• postpathological
  adjective
• semipathologic
  adjective
• semipathological
  adjective
• unpathological
  adjective
• nonpathologically
  adverb
• pathologically
  adverb
• semipathologically
  adverb
• unpathologically
  adverb

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Etymology

Origin of pathological

First recorded in 1680–90; from Greek pathologik(ós) ( see pathology, -ic) + -al ¹

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Explanation

If something is caused by a physical or mental disease, it is pathological. Someone with a pathological compulsion for cleanliness might scrub the floors for hours every night. Pathological comes from a Greek word, pathologikos, which means “treating of diseases” — pathos means "suffering." Anyone who studies or works with diseases, from their causes to their symptoms, identifies how the disease affects its victims, in other words, its pathological effects. Remember that this is a medical distinction. If a person has, for example, obsessive-compulsive disorder, his or her repetitive actions are pathological.

Example Sentences

See Examples For:

pathological

I want to send the message that she’d better keep my name out of her mouth because I do think she is a pathological liar.

From MarketWatch ● Aug. 29, 2026

"GAE is a whole new treatment regimen that targets abnormal hypervascularity around the joint and, in turn, modulates the pathological neurovascular environment," Dr. Fleckenstein said.

From Science Daily ● Jun. 17, 2026

Federal prosecutors called him a pathological liar and swindler who falsely portrayed himself as a successful businessman and real-estate mogul with stints at Citigroup and Goldman Sachs.

From The Wall Street Journal ● Jun. 3, 2026

As a result, Prof Voon says, friends or family can regard the change in behaviour as generosity or extravagance - rather than anything pathological - and so it continues.

From BBC ● May 1, 2026

Moose are large, and essentially insane with an almost pathological hatred of the dogs, the sled, the musher, trees, trains, cars, and everything else as near as I can figure.

From "Woodsong" by Gary Paulsen

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