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.
Why cruise ships are battling a so many norovirus outbreaks Fifty-five of the 1,149 guests aboard the line’s Zuiderdam ship also got sick during its current cruise, in addition to 14 crew, with their main symptom being diarrhea. Nathan Diller, USA Today, 29 Apr. 2025 Dozens of Hikers Fall Ill with Norovirus, Force Temporary Closure of Popular Hawaii Hiking Trail Earlier this month, over 200 passengers and 17 crew aboard a Cunard Line ship reported being ill following a norovirus outbreak. Kimberlee Speakman, People.com, 23 Apr. 2025 On average, some 19-21 million instances of norovirus illness occur in the US every year, according to the CDC. Francesca Street, CNN Money, 2 Apr. 2025 The news follows three other norovirus outbreaks on Holland America ships this year, including another on Rotterdam last month. Nathan Diller, USA TODAY, 18 Mar. 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 24 May. 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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