norovirus

noun

nor·​o·​virus ˈnȯr-ə-ˌvī-rəs How to pronounce norovirus (audio)
: any of a genus (Norovirus) of small, round, single-stranded RNA viruses that includes a single species (species Norwalk virus) with various strains causing gastroenteritis in people and animals (such as cows, pigs, and dogs)
People spread the virus by eating food or drinking liquids that are contaminated with norovirus, touching surfaces or objects contaminated with norovirus and then touching their mouth or having direct contact with another person who is infected.Cherie Black

Note: In people, noroviruses cause gastroenteritis marked chiefly by sudden onset diarrhea, vomiting, nausea, and abdominal cramps.

see norwalk virus

Examples of norovirus 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.
In fact, this is the 14th norovirus outbreak so far in 2025 aboard a cruise ship within the Vessel Sanitation Program’s jurisdiction.3 That’s because the virus is highly contagious. Jenna Anderson, Health, 4 Oct. 2025 The Royal Caribbean cruise ship facing a norovirus outbreak while at sea docked at PortMiami early Thursday morning, concluding a 13-night voyage. Miami Herald, 3 Oct. 2025 Royal Caribbean International’s Serenade of the Seas cruise ship was hit with a norovirus outbreak that has sickened nearly 100 people. Ashley J. Dimella, FOXNews.com, 3 Oct. 2025 It can be caused by viruses such as the norovirus, bacteria such as E. coli, parasites including giardia, and certain medicines or toxins. Chandelis Duster, NPR, 27 July 2025 See All Example Sentences for norovirus

Word History

Etymology

New Latin, from English Norwalk virus + New Latin -o- + virus

First Known Use

2002, in the meaning defined above

Time Traveler
The first known use of norovirus was in 2002

Browse Nearby Words

Cite this Entry

“Norovirus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/norovirus. Accessed 18 Oct. 2025.

Medical Definition

norovirus

noun
nor·​o·​virus ˌnȯr-ō-ˈvī-rəs How to pronounce norovirus (audio)
1
capitalized : a genus of small, round, single-stranded, highly infectious RNA viruses that includes a single species (species Norwalk virus) with various strains causing gastroenteritis in people and animals (such as cows and dogs)
2
: any virus of the genus Norovirus
People spread the virus by eating food or drinking liquids that are contaminated with norovirus, touching surfaces or objects contaminated with norovirus and then touching their mouth or having direct contact with another person who is infected.Cherie Black, The Seattle Post-Intelligencer

Note: In people, noroviruses cause gastroenteritis marked chiefly by sudden onset, diarrhea, vomiting, nausea, and abdominal cramps.

see norwalk virus
Last Updated: - Updated example sentences
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