Comedogenic

Part of speech: adjective

Definitions

1. Describing ingredients or agents likely to obstruct skin pores, cause pimple outbreaks, or increase susceptibility to acne formation
2. Likely to clog skin pores and promote the development of acne or pimples
3. Having a property that increases the chance of skin blemishes by blocking pores

Etymology: "Comedogenic" is built from "comedo," a term for a blackhead, plus the suffix "-genic," meaning "producing" or "giving rise to." The "comedo" part comes from Latin "comedo," literally "glutton" or "one who eats up," which is the word's central surprise: a clogged pore was named for something that devours. The Latin noun was formed from "comedere," "to eat up," from "com-" plus "edere," "to eat." The suffix has a longer ancestry. It descends from Ancient Greek "-genēs" and "génos," meaning "birth" or "kind," and reached English through Latin "-icus" and Old French "-ique," which gave Middle English "-ik." English then reshaped it into "-ic," and added "-genic" to form words such as this one. Put together, "comedogenic" describes a substance that produces blackheads. It is a modern coinage built from classical parts, so the Romans and Greeks would not have recognised it, though they supplied every piece.