Corneae

Part of speech: noun

Definitions

1. The transparent front part of the eye that covers the iris and pupil while aiding in focusing light onto the retina
2. The dome-shaped structure of the eye providing protection and playing a key role in vision by refracting light
3. A crucial component of the eye, essential for sight, that serves both a protective and refractive function

Etymology: "Corneae" is the Latin plural of "cornea," so it is the form English uses when speaking of more than one of these structures, one in each eye. The singular "cornea" comes from the Latin adjective "corneus," meaning "horny" or "made of horn," which in turn derives from "cornu," horn. The eye's clear front layer was named for its resemblance to horn, a material that was thin, translucent and tough, and Latin-writing anatomists applied the adjective to that tissue. Because the word is a Latin plural form, English speakers who use it in the plural are keeping the original Latin inflection rather than adding a regular English "-s." The same pattern appears in other anatomical borrowings, where the plural retains the Latin ending.

Synonyms: corneas, eye corneas