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

More than 100 passengers and crew fell sick during a norovirus outbreak aboard the Caribbean Princess cruise ship. —Kayla Hayempour, NBC news, 10 May 2026

The outbreak on the Caribbean Princess comes more than a month after another norovirus outbreak was reported on another Princess ship. —Matthew Ablon, CBS News, 9 May 2026

Over 100 people were affected by a norovirus outbreak aboard the Caribbean Princess cruise, according to a Centers for Disease Control and Prevention (CDC) report released Thursday. —Brittany Miller, FOXNews.com, 8 May 2026

More than 100 people have been sickened in a norovirus outbreak on board a Caribbean Princess cruise, according to the Centers for Disease Control and Prevention. —Clara McMichael, ABC News, 8 May 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