lesion

noun

le·​sion ˈlē-zhən 

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 

adjective

Examples of lesion in a Sentence

Recent Examples on the Web

In January, he was told that there were some signs of improvement in his lungs and that the lesions in his brain — which were being treated by an outside radiation oncologist — were disappearing. — Trisha Thadani Kirsten Potter Tanya Pérez Devin Murphy, New York Times, 4 Oct. 2026

Symptoms of the disease include severe itching and disfiguring skin conditions, as well as visual impairment and even permanent blindness after lesions develop on one’s eyes. — Tabitha Parent, PEOPLE, 28 Sep. 2026

Radiological scans also confirmed lesions on the dog’s right shoulder, and Cotelo recommended an operation to scrape the excess cartilage, Shin said. — David Goodhue, Miami Herald, 23 Sep. 2026

Armstrong underwent excision surgery, a procedure to remove endometriosis lesions and scar tissue. — Laura Ungar, Los Angeles Times, 8 Sep. 2026

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

Rhymes for lesion

• friesian
• adhesion
• artesian
• cartesian
• cohesion
• elysian
• magnesian
• austronesian
• indonesian
• melanesian
• micronesian
• polynesian

Kids Definition

lesion

noun

le·​sion ˈlē-zhən 

: 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 

: 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 

adjective

lesion

2 of 2 transitive verb

: to produce lesions in (as an animal's brain)

Legal Definition

lesion

noun

le·​sion ˈlē-zhən 

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