COVID-19

American  

[koh-vid-nahyn-teen] / ˈkoʊ vɪd naɪnˌtin /

Also Covid-19;

noun

Pathology.

1. coronavirus disease 2019: a potentially severe, primarily respiratory illness caused by a coronavirus and characterized by fever, coughing, and shortness of breath. In some people, the disease also damages major organs, as the heart or kidneys.

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Spelling

COVID-19 (all capital letters) is the spelling used internationally by scientific and medical professionals and their related organizations, which corresponds with the American convention of capitalizing an acronym such as AIDS or SARS. However, Covid-19 (spelled like a proper noun with an initial capital letter followed by lowercase letters) is the less obtrusive form used by several prominent media, such as The New York Times and The Times of London. And it is not uncommon to see both forms shortened to just COVID or Covid, respectively. The lowercase form covid is considerably less common in edited text.

Usage

What is COVID-19?  COVID-19 is a highly infectious respiratory disease caused by a new coronavirus. The disease was discovered in China in December 2019 and then spread around the world, causing an unprecedented public health crisis. For health, safety, and medical emergencies or updates on the novel coronavirus pandemic, please visit the CDC (Centers for Disease Control and Prevention) and WHO (World Health Organization). What are some variants of COVID-19?

• Covid-19
• covid-19
• COVID
• covid

Etymology

Origin of COVID-19

Short for co(rona)vi(rus) d(isease) (20)19, the year in which the outbreak of the disease was first identified; so named by the World Health Organization in 2020

Example Sentences

The last al-Qaida-connected attack within the U.S. occurred before the COVID-19 pandemic.

From Slate • Apr. 21, 2026

During the COVID-19 pandemic, when lab work paused, he spent time reviewing scientific literature and noticed something unexpected.

From Science Daily • Apr. 20, 2026

A highly mutated COVID-19 strain is circulating in California — raising concerns that disease activity could rise heading into the summer.

From Los Angeles Times • Apr. 20, 2026

Lipid nanoparticles, or LNPs, are best known for their role in delivering the COVID-19 mRNA vaccines given to billions of people.

From Science Daily • Apr. 20, 2026

Demand is forecast to fall by 1.5 million barrels a day in the second quarter, the sharpest decline since the COVID-19 pandemic.

From MarketWatch • Apr. 14, 2026