lesion

noun

le·​sion ˈlē-zhən How to pronounce lesion (audio)
1
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 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.
Her eldest daughter, 15-year-old Camille, has a brain lesion that causes severe epilepsy and needs to stay close to her neurologist. Lauren Villagran, USA Today, 26 Oct. 2025 Follow-up MRIs during the next several years showed no new lesions on my brain or my spine. Lucinda Rosenfeld, New Yorker, 25 Oct. 2025 It may be yellowed, have dark spots or sunken lesions, Kondrat says. Leanne Potts, Better Homes & Gardens, 23 Oct. 2025 Previously, during a routine physical in 2023, another cancerous skin lesion had been successfully removed with similar follow-up. Gabe Whisnant, MSNBC Newsweek, 20 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Lesion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lesion. Accessed 29 Oct. 2025.

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 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

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