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

The co-stars reminisced about their chemistry onset and the impact of the film decades later. Erica Gonzales, Harper's BAZAAR, "Meg Ryan and Billy Crystal Sweetly Reunite for the 30th Anniversary of When Harry Met Sally," 12 Apr. 2019 Serious but rare side effects include delayed onset infections, recurrence of herpetic eruptions, and superficial necrosis at the injection site. Vogue, "Celebrity Manicurist Deborah Lippmann on Beauty, Aging, and the Product That Changed her Relationship With her Hands," 1 Apr. 2019 In the second study, also published in Gastroenterology, Mayo Clinic researchers describe a risk-prediction model that identifies patients with new onset diabetes that are at very high risk for developing pancreatic cancer. Mayo Clinic News Network, chicagotribune.com, "Mayo researchers identify method to diagnose pancreatic cancer in patients with early onset diabetes," 26 June 2018 The hairstylist onset of Shadowhunters would use the product on her locks each day. Nicole Saunders, Harper's BAZAAR, "Watch Kat McNamara's Nighttime Beauty Routine," 12 Mar. 2019 The month of May, before the onset of the rainy season, is the best month for climbing Everest. Author: Gopal Sharma, Anchorage Daily News, "Australian who climbed Denali in April sets Seven Summits record on Everest," 14 May 2018 Wittenberg hadn't so much as broken a bone before the onset of the disease. Ben Brazil, latimes.com, "UC Irvine medical study gives hope to Orange County mom with ALS," 19 Apr. 2018 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

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

6 May 2019

Look-up Popularity

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 sum of money that is sent as a payment

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