Meaning

noun any localized abnormal structural change in a bodily part

noun an injury to living tissue (especially an injury involving a cut or break in the skin)

originFrom Middle English lesioun (“physical injuring of the body”), from Old French lesion (“hurt, offense, wrong, injury, wound”), from Latin laesiō (“hurt, harm, injury”) (whence -ion (“noun suffix denoting action, result, process, state, condition”)), from laesus (“hurt, injured, wounded, damaged”), past participle of laedō (“to strike, collide, hurt”).

Etymology from Wiktionary, CC BY-SA 3.0