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1835, inflammation of the conjunctiva; from conjunctiva + -itis.
conjunctivitis con·junc·ti·vi·tis (kən-jŭngk'tə-vī'tĭs)n. Inflammation of the conjunctiva, characterized by redness and often accompanied by a discharge.
Inflammation of the conjunctiva, the transparent mucous membrane that lines the inner surface of the eyelid and covers the front part of the eyeball. Often called pinkeye.