onset

noun

on·​set ˈȯn-ˌset How to pronounce onset (audio)
ˈän-
1
: attack, assault
withstand the onset of the army
2
: beginning, commencement
the onset of winter
the onset of age-related diseases

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
For example, the American Cancer Society reports that early onset colorectal cancer cases in adults younger than 50 grew by 2.4% each year from 2012-2021. The Editorial Board, Chicago Tribune, 27 Jan. 2025 But from the onset, the second-oldest republic in the Western Hemisphere after the United States was beset by armed conflict, foreign interventions, repressive dictators, political violence, and heads of state whose personal ambitions and desire for power fanned instability and revolts. Jacqueline Charles, Miami Herald, 26 Jan. 2025 From the onset, Unkovski introduces a rich soundtrack that mixes modern English-language songs with tracks specific to the region, as well as Alen Sinkauz and Nenad Sinkauz’s larger-than-life score, which sounds as if Ahmet were a mythical paladin on a quest. Carlos Aguilar, Variety, 25 Jan. 2025 But conditions like an overactive thyroid, menopause, or early onset of a serious infection can, too, Gee says. Angela Haupt, TIME, 24 Jan. 2025 See all Example Sentences for onset 

Word History

First Known Use

circa 1522, in the meaning defined at sense 1

Time Traveler
The first known use of onset was circa 1522

Dictionary Entries Near onset

Cite this Entry

“Onset.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onset. Accessed 1 Feb. 2025.

Kids Definition

onset

noun
on·​set ˈȯn-ˌset How to pronounce onset (audio)
ˈän-

Medical Definition

onset

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

More from Merriam-Webster on onset

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