Comedo

Part of speech: noun

Pronunciation: /ˈkɒmədəʊ/

Definitions

1. An obstructed hair follicle that can lead to acne forms as a type of skin lesion resulting from the buildup of oils and dead skin cells
2. A skin condition manifests as a clogged pore filled with keratin and sebum, often associated with acne
3. A hair follicle blocked by excess sebum and keratin causing a skin blemish commonly linked to acne

Etymology: The Latin "comedō" meant "glutton" or "one who eats up", a derivative of "comedere", to eat up. Its medical use in English rests on a belief that seemed reasonable to early physicians. Blackheads looked like tiny dark hairs lodged in the skin, and they were thought to be worms that fed on the body. In German lexicons of the early eighteenth century, "Mitesser", literally "along-eaters", named these supposed worms, which were blamed for children's weight loss, crying and sleeplessness. Latin scholars rendered the German term as "comedones", borrowing the glutton's name for the creatures. The worm theory was not universal. A 1721 lexicon by Johann Theodor Jablonski, which listed "comedones" alongside "vermiculi cutanei" ("skin-worms"), also offered a more sensible explanation: the spots formed from a fatty, raw humour that could not escape through blocked sweat pores. That account anticipates the modern understanding of clogged follicles, even though the Latin name kept the older idea of a devouring creature.

Synonyms: blackhead, whitehead, pimple, acne, zit