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 stages are primarily based on the amount, depth, and location of endometriosis lesions, as well as the presence of scar tissue and adhesions. — Anthony Robledo, USA Today, 4 Aug. 2026 Those lesions can trigger issues with balance, vision, speech, dizziness and more, according to MS Trust. — Vanessa Etienne, PEOPLE, 29 July 2026 It was later found that 23% to 37% of those sampled had confirmed melanoma lesions, a type of skin cancer, according to a new study published in Nature. — Dr. Yonathan Daniel, ABC News, 25 July 2026 However, a person with suspicious lesions should seek immediate medical attention. — Sarah Tomlinson, The Conversation, 24 July 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 5 Aug. 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

Nglish: Translation of lesion for Spanish Speakers

Britannica.com: Encyclopedia article about lesion

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