rotavirus

noun

ro·​ta·​vi·​rus ˈrō-tə-ˌvī-rəs How to pronounce rotavirus (audio)
plural rotaviruses
: any of a genus (Rotavirus) of reoviruses that have a three-layered protein capsid with no outer lipid envelope when mature and that include one (Rotavirus alphagastroenteritidis) causing epidemics of severe and sometimes fatal diarrhea in infants and young children

Examples of rotavirus 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.
There are two rotavirus vaccines – Rotateq (a three-dose series) and Rotarix (a two-dose series). — Melissa Rudy, FOXNews.com, 23 Apr. 2026 The most common complication from rotavirus is dehydration, the clinic said. — Don Sweeney, Sacbee.com, 27 May 2026 Recent rotavirus surge Rotavirus is a springtime illness in America. — Annette Regan, The Conversation, 22 Apr. 2026 The percentage of positive rotavirus tests across the country has been steadily increasing since January. — Devika Rao, TheWeek, 22 Apr. 2026 See All Example Sentences for rotavirus

Word History

Etymology

New Latin, from Latin rota wheel + New Latin virus

First Known Use

1974, in the meaning defined above

Time Traveler
The first known use of rotavirus was in 1974

Rhymes for rotavirus

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Browse Nearby Words

rotatory reflection axis
rotavirus
Rotblat
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Cite this Entry

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

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Medical Definition

rotavirus

noun
ro·​ta·​vi·​rus ˈrōt-ə-ˌvī-rəs How to pronounce rotavirus (audio)
1
Rotavirus : a genus of reoviruses that are causative agents of gastroenteritis and that include one (Rotavirus alphagastroenteritidis) causing epidemics of severe and sometimes fatal diarrhea in infants and young children

Note: Viruses of the genus Rotavirus have a virion with a three-layered protein capsid lacking an outer lipid envelope when mature and a core of 11 discrete segments of double-stranded RNA.

2
: any virus of the genus Rotavirus
rotaviral
-rəl How to pronounce rotavirus (audio)
adjective
Last Updated: - Updated example sentences
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