on·​set | \ ˈȯn-ˌset How to pronounce onset (audio) , ˈän-\

Definition of onset

1 : attack, assault withstand the onset of the army
2 : beginning, commencement the onset of winter the onset of age-related diseases

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Examples of onset in a Sentence

the walls withstood the onset of the first battalion the claim that if you take enough vitamin C at the onset of a cold, you'll often recover faster

Recent Examples on the Web

Ty Dolla $ign & Valee) Burgeoning G.O.O.D Music signee and Chi-town native Valee teams with R&B star Ty Dolla $ign to set the tone for the track filled with a thundering church organ at its onset. Michael Saponara, Billboard, "Ranking Every Song From Kanye West's 'Ye' Album: Critic's Picks," 1 June 2018 How, amid all the ads regarding wrinkles, veins, dark spots, fine lines, lasers, and Botox, had I not been primed to fear and track their onset? Nicole Hardy, Marie Claire, "I Was 36 Years Old and Had Never Had Sex Before—and Then Things Got Awkward," 28 June 2016 Either way, the onset of a new year is like a blank canvas ready to be filled with your ideas. Maya Allen, Marie Claire, "Beyoncé's Makeup Artist Says These Will Be the Coolest Makeup Trends of 2019," 23 Jan. 2019 This jibes chronologically with the onset of the Black Death; and plague could have continued traversing this route with the fur traders for centuries. Diana Gitig, Ars Technica, "Medieval European plague genomes hint at Black Death’s travels," 5 Dec. 2018 These symptoms are essentially the same as the ones present for type 2 diabetes, but the Mayo Clinic notes that their onset can occur faster in type 1 patients, and may even feel more aggressive. Colleen Stinchcombe, Woman's Day, "What's the Difference Between Type 1 and Type 2 Diabetes?," 10 Sep. 2018 Obviously, Queen Bee is well aware of Minaj's career as the pair of rap stars have clashed since the onset of the decade. Michael Saponara, Billboard, "Lil Kim Says She Doesn't Know Who Nicki Minaj Is, Shows Love to Cardi B: Watch," 22 June 2018 But with the onset of a military offensive, HTS has set up joint operation rooms with different National Front factions. Fox News, "Last stand: Syria's rebel Idlib prepares for a losing battle," 16 Sep. 2018 Another theory holds that, at night, people with asthma may have higher than usual numbers of various kinds of white blood cells linked with the onset of asthma symptoms. Korin Miller, SELF, "Here’s Why Your Asthma Gets Worse at Night," 26 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'onset.' 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 onset

circa 1522, in the meaning defined at sense 1

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Statistics for onset

Last Updated

11 Mar 2019

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Time Traveler for onset

The first known use of onset was circa 1522

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More Definitions for onset



English Language Learners Definition of onset

: the beginning of something


on·​set | \ ˈȯn-ˌset How to pronounce onset (audio) , ˈän-\

Kids Definition of onset

1 : beginning sense 1 the onset of winter


on·​set | \ ˈȯn-ˌset, ˈän- How to pronounce onset (audio) \

Medical Definition of onset

: the initial existence or symptoms of a disease the onset of scarlet fever

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More from Merriam-Webster on onset

Rhyming Dictionary: Words that rhyme with onset

Thesaurus: All synonyms and antonyms for onset

Spanish Central: Translation of onset

Nglish: Translation of onset for Spanish Speakers

Britannica English: Translation of onset for Arabic Speakers

Comments on onset

What made you want to look up onset? Please tell us where you read or heard it (including the quote, if possible).


a shady place in a garden or forest

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