pathological

adjective

path·​o·​log·​i·​cal ˌpa-thə-ˈlä-ji-kəl How to pronounce pathological (audio)
variants or less commonly pathologic
1
: of or relating to pathology
pathological research
A pathological examination led to the diagnosis.
2
: altered or caused by disease
pathological changes in the body
also : indicative of disease
pathological symptoms
3
: being such to a degree that is extreme, excessive, or markedly abnormal
a pathological liar
pathological fear
pathologically adverb

Examples of pathological in a Sentence

He is a pathological liar. She has a pathological fear of heights. pathological changes in the body
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In this case, the researchers suggest that the abnormal theta-alpha coupling may reflect a pathological neural signature of OCD. New Atlas, 3 Aug. 2025 If the amyloid diagnosis is confirmed, patients can be prescribed one of two monoclonal antibodies, both FDA-approved in 2023, that can slow disease progression by targeting and removing pathological amyloid deposits in the brain. Juergen Eckhardt, Forbes.com, 22 July 2025 Our nation is arguably helped when Newsom’s most unbelievable and pathological tendencies are on full public display. Will O’Neill, Oc Register, 18 July 2025 Dermatologists typically cite factors such as genetics, UV damage, and underlying pathological conditions. Andrew Paul, Popular Science, 23 July 2025 See All Example Sentences for pathological

Word History

Etymology

New Latin pathologicus "of the study of the passions, of the study of diseases" (borrowed from Greek pathologikós, from patho- patho- + -logikos, from -logia -logy + -ikos -ic entry 1) + -al entry 1

First Known Use

1656, in the meaning defined at sense 1

Time Traveler
The first known use of pathological was in 1656

Browse Nearby Words

Cite this Entry

“Pathological.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pathological. Accessed 19 Aug. 2025.

Kids Definition

pathological

adjective
patho·​log·​i·​cal
ˌpath-ə-ˈläj-i-kəl
variants also pathologic
-ik
1
: of or relating to pathology
2
: changed or caused by disease
3
: being such to a degree that is extreme, excessive, or abnormal
a pathological liar
pathologically
-i-k(ə-)lē
adverb

Medical Definition

pathological

adjective
patho·​log·​i·​cal ˌpath-ə-ˈläj-i-kəl How to pronounce pathological (audio)
variants also pathologic
1
: of or relating to pathology
a pathological laboratory
2
: altered or caused by disease
pathological tissue
also : indicative of disease
pathological lesions
pathologically adverb

More from Merriam-Webster on pathological

Last Updated: - Updated example sentences
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