What does entropion mean?
Entropion is a medical term for an eyelid that has turned inward, so that the skin and lashes of the lid margin rest against the surface of the eye rather than away from it. The constant friction between the lashes and the cornea or conjunctiva causes irritation, redness, excessive tearing, and, if left untreated, can scratch and scar the cornea and impair vision. It most often affects the lower eyelid and arises chiefly in older adults from age-related loosening of the lid tissues, though scarring from injury, infection, or inflammation can produce it at any age. Treatment typically involves lubricating drops, taping, or corrective surgery that restores the lid to its normal position. Though unfamiliar outside clinical settings, entropion is a precise and useful word for describing this common and treatable eye condition.
nounA medical condition in which the margin of the eyelid turns inward against the eyeball, causing the lashes to rub on the cornea.
- A medical condition in which all or part of the eyelid margin rotates inward so that the lashes rub against the cornea or conjunctiva.
"The elderly patient's chronic entropion required minor surgery to prevent corneal damage."
"Age-related laxity of the lower lid led to involutional entropion, making her eye water constantly."
"After the burn scar contracted, cicatricial entropion developed and threatened his vision."
Rarely pluralized since the word usually refers to the condition generically; the plural appears mainly when discussing multiple cases.
"The clinic treated several entropions resulting from trachoma scarring."
The word for an eyelid rolling inward comes from the same Greek root as 'heliotrope' — a plant that turns to face the sun — because both are about which way something turns.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of entropion
Entropion derives from Greek 'entropē', meaning 'a turning in' or inversion, formed from 'en-' ('in') plus 'tropē' ('a turn'), the same root seen in 'trope', 'tropic', 'heliotrope', and 'entropy'. It entered English medical vocabulary in the 18th century via New Latin usage in anatomy and ophthalmology texts. Its natural counterpart, 'ectropion' (outward turning), was coined on the same pattern, reflecting how classical roots were systematically combined to name anatomical deviations.
How entropion is actually used
A technical term used almost exclusively in ophthalmology and medicine; rare in general conversation. It carries no figurative or informal use. The plural is uncommon but follows regular English patterns.
Easily confused with entropion
Ectropion is the opposite condition — the eyelid turns outward and away from the eye, whereas entropion turns it inward toward the eye.