lesion

noun

le·​sion ˈlē-zhən How to pronounce lesion (audio)
Synonyms of lesionnext
1
: injury, harm
2
: an abnormal change in structure of an organ or part due to injury or disease
especially : one that is circumscribed (see circumscribe sense 1) and well-defined
lesioned
ˈlē-zhənd How to pronounce lesion (audio)
adjective

Examples of lesion in a Sentence

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.
The stars have grown lethargic and limp, with lesions spread across their bodies, their arms falling off or disintegrating. — Joseph Ogilvy, Condé Nast Traveler, 28 Oct. 2026 First, cats started showing up to the city’s clinics very sick and covered with lesions. — Dominique Mosbergen, Time, 27 Oct. 2026 One particularly promising example is an MRI technique that identifies the central vein sign, a feature that can help physicians distinguish lesions associated with MS from abnormalities caused by other conditions. — Bruce Bebo, STAT, 24 Oct. 2026 Newer imaging techniques may help doctors distinguish MS lesions from white matter spots caused by other conditions. — Melissa Rudy, FOXNews.com, 24 Oct. 2026 See All Example Sentences for lesion

Word History

Etymology

Middle English, from Anglo-French, from Latin laesion-, laesio, from laedere to injure

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of lesion was in the 15th century

Rhymes for lesion

See All Rhymes for lesion

Browse Nearby Words

Lesghian
lesion
Leskeaceae
See all Nearby Words

Cite this Entry

“Lesion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lesion. Accessed 30 Oct. 2026.

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Kids Definition

lesion

noun
le·​sion ˈlē-zhən How to pronounce lesion (audio)
: a change in the structure of a bodily organ or part due to injury or disease
especially : an injured or diseased spot or area clearly marked off from healthy tissue around it

Medical Definition

lesion

1 of 2 noun
le·​sion ˈlē-zhən How to pronounce lesion (audio)
: an abnormal change in structure of an organ or part due to injury or disease
especially : one that is circumscribed and well defined
lesioned
-zhənd How to pronounce lesion (audio)
adjective

lesion

2 of 2 transitive verb
: to produce lesions in (as an animal's brain)

Legal Definition

lesion

noun
le·​sion ˈlē-zhən How to pronounce lesion (audio)
in the civil law of Louisiana : loss from failure to receive a threshold amount or value (as one-half market value) for immovable property conveyed or transferred by a commutative contract (as a sale or exchange)

called also lesion beyond moiety

compare unjust enrichment
Etymology

Anglo-French, damage, injury, from Latin laesio, from laedere to injure

More from Merriam-Webster on lesion

Thesaurus: All synonyms and antonyms for lesion

Britannica.com: Encyclopedia article about lesion

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