conjunctivitis

noun

: inflammation of the conjunctiva

Word History

First Known Use

1835, in the meaning defined above

Time Traveler
The first known use of conjunctivitis was in 1835

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Cite this Entry

“Conjunctivitis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/conjunctivitis. Accessed 22 Oct. 2026.

Kids Definition

conjunctivitis

noun
: inflammation of the conjunctiva : pinkeye

Medical Definition

conjunctivitis

noun
: inflammation of the conjunctiva that is typically marked by pinkness or redness of the sclera and by itching, burning, irritation, discharge, or excessive tearing of the eye and that is typically caused by pathogenic microorganisms (such as bacteria or viruses), allergens, or irritants see pink eye

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