norovirus

noun

nor·​o·​vi·​rus ˈnȯr-ə-ˌvī-rəs 

plural noroviruses

: any of a genus (Norovirus) of small, round, single-stranded RNA viruses that includes a single species (N. norwalkense) 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

Cruises have hit the headlines for this year, from Hantavirus scares to a norovirus outbreak that authorities in Bordeaux to deny anyone disembarkation from an Ambassador Cruise Line ship in May. — Julia Buckley, CNN Money, 6 July 2026

Meanwhile, another cruise ship heading to Alaska at the end of June also experienced a norovirus outbreak. — Adam England, PEOPLE, 3 July 2026

More than 120 people got sick in a norovirus outbreak aboard a Princess Cruises ship, marking the cruise line’s third this year. — Nathan Diller, USA Today, 2 July 2026

More than 100 passengers were sickened in a recent norovirus outbreak on the Ruby Princess cruise ship that departed from California last month and arrived back at port Thursday. — Alex Wigglesworth, Los Angeles Times, 2 July 2026

Word History

Etymology

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

First Known Use

2002, in the meaning defined above

Rhymes for norovirus

• antivirus
• herpesvirus
• parvovirus
• reovirus
• retrovirus
• rhinovirus
• rotavirus
• adenovirus
• baculovirus
• coronavirus
• enterovirus
• poliovirus

Medical Definition

norovirus

noun

nor·​o·​virus ˌnȯr-ō-ˈvī-rəs 

1

Norovirus : a genus of caliciviruses that includes a single species (Norovirus norwalkense) with various strains causing gastroenteritis in people and animals (such as cows and dogs)

2

: any virus of the genus Norovirus

Norovirus can be transmitted person-to-person (via the fecal-oral route) and spread through contaminated airborne droplets, food, water, environmental surfaces, and fomites.

—The Journal of the American Medical Association

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

see norwalk virus