mastitis

noun

mas·​ti·​tis ma-ˈstī-təs How to pronounce mastitis (audio)
plural mastitides ma-ˈsti-tə-ˌdēz How to pronounce mastitis (audio)
: inflammation of the breast or udder usually caused by infection
mastitic
ma-ˈsti-tik How to pronounce mastitis (audio)
adjective

Examples of mastitis in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The horse has mastitis, and James takes care of it, so that’s fine, and Tristan does not get to play croquet because of something to do with the grass. — Alice Burton, Vulture, 9 Feb. 2026 The disease can also cause oophoritis or mastitis, which respectively mean inflammation in the ovaries or breasts. — Tanya Lewis, Scientific American, 6 Mar. 2026 These mothers shared vulnerable, deeply personal thoughts about topics such as mastitis and feeling annoyed with their kids, but they largely weren’t getting paid. — Kristen Martin, The Atlantic, 13 May 2026 Women suffering from mastitis may also experience breast tenderness and redness, skin changes, fever, or chills. — Melissa Willets, Parents, 13 Nov. 2025 See All Example Sentences for mastitis

Word History

Etymology

Greek mastós "breast, nipple" (probably from a pre-Greek substratal language) + -itis, probably after French mastite

First Known Use

circa 1842, in the meaning defined above

Time Traveler
The first known use of mastitis was circa 1842

Rhymes for mastitis

See All Rhymes for mastitis

Browse Nearby Words

mastika
mastitis
-mastix
See all Nearby Words

Cite this Entry

“Mastitis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mastitis. Accessed 7 Jul. 2026.

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Medical Definition

mastitis

noun
mas·​ti·​tis ma-ˈstīt-əs How to pronounce mastitis (audio)
plural mastitides -ˈtit-ə-ˌdēz How to pronounce mastitis (audio)
: inflammation of the mammary gland or udder usually caused by infection

called also mammitis

see blue bag, bovine mastitis, garget, summer mastitis

More from Merriam-Webster on mastitis

Britannica.com: Encyclopedia article about mastitis

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