om·​i·​cron | \ ˈä-mə-ˌkrän How to pronounce omicron (audio) , ˈō-mə-ˌkrän How to pronounce omicron (audio) , British ō-ˈmī-(ˌ)krän \

Definition of omicron

: the 15th letter of the Greek alphabet — see Alphabet Table

How a Virus Got Its Name: Usage Guide

In November 2021, a COVID-19 variant was named Omicron, after the 15th letter of the Greek alphabet. The World Health Organization uses Greek letters to name variants, because these names are easier to communicate than scientific designations like B.1.617.2. According to the WHO, the 13th and 14th Greek letters (nu and xi) were skipped over because “nu” sounds like “new,” and “xi” is also a common surname.

How to Pronounce Omicron: Usage Guide

The pronunciation of omicron has several variant forms acceptable in standard English. In American English, the primary stress is usually on the first syllable, pronounced as either a short \o\ as \AH-muh-krahn\ or a long \o\ as \OH-muh-krahn\. In British English, the primary stress can also be heard on the second syllable: \oh-MYE-krahn\.

Examples of omicron in a Sentence

Recent Examples on the Web More:Looking for a consistent school response to the omicron surge? Alec Johnson, Milwaukee Journal Sentinel, 21 Jan. 2022 Obviously talking about live in-person events feels a bit strange at the moment, given the omicron surge and how the rise in COVID-19 cases has forced January and February events to be postponed, canceled or moved to virtual. Michael Schneider, Variety, 20 Jan. 2022 The omicron surge has put growing stress on the region's 40 hospitals, with 4 of every 10 patients now suffering from the novel coronavirus. Brooks Sutherland, The Enquirer, 20 Jan. 2022 With the omicron surge still straining hospitals across America, addressing vaccine hesitancy remains a crucial discussion. Dr. Aubrie Ford, ABC News, 20 Jan. 2022 British Prime Minister Boris Johnson will attempt to end all COVID-19 restrictions by March after insisting that the nation’s omicron surge has peaked. Peter Aitken, Fox News, 20 Jan. 2022 Omicron down: Data shows that the COVID-19 omicron surge that began in late December in Cuyahoga County and Northeast Ohio appears to be over. Jeremy Pelzer, cleveland, 20 Jan. 2022 As such, the findings cannot be applied to the current omicron variant surge, which accounts for more than 99 percent of new Covid cases in the United States. NBC News, 20 Jan. 2022 Florida’s omicron surge continued to ease as the state’s 7-day average for new cases declined for the eight consecutive day and the number of patients in the hospital with COVID-19 remained stable, federal data shows. David Schutz,, 19 Jan. 2022

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'omicron.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of omicron

15th century, in the meaning defined above

History and Etymology for omicron

Middle English, from Greek o mikron, literally, small o

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Time Traveler for omicron

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The first known use of omicron was in the 15th century

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Omicron Ceti

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Last Updated

22 Jan 2022

Cite this Entry

“Omicron.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2022.

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