blackhead

== English == === Etymology === From black +‎ head. === Pronunciation === IPA(key): /ˈblæk.hɛd/ === Noun === blackhead (countable and uncountable, plural blackheads) (countable, medicine) A type of comedo, a skin blemish, a type of acne vulgaris, where a pore becomes clogged with a dark, hard, cheesy keratin-filled substance forming a hard black "head" on the skin's surface. Synonym: open comedo Coordinate term: whitehead (uncountable) A form of histomoniasis in poultry, characterized by cyanotic discoloration on the bird's head. (countable) A scaup: any of various ducks of the genus Aythya. ==== Derived terms ==== blackheaded (second sense) ==== Translations ==== ==== Further reading ==== blackhead on Wikipedia.Wikipedia Blackhead in the 1920 edition of Encyclopedia Americana.