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"blackhead," etc., 1866, from Latin comedo "glutton," from comedere "to eat up" (see comestible). A name formerly given to worms that devour the body; transferred in medical use to secretions that resemble them.
comedo com·e·do (kŏm'ĭ-dō')
n. pl. com·e·dos or com·e·do·nes (-dō'nēz)
A blackhead and the primary lesion of acne vulgaris.