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.
What's especially remarkable is that the system can recreate the user's own voice, thanks to a voice cloning algorithm trained on recordings made before the onset of ALS. Kurt Knutsson, FOXNews.com, 1 July 2025 Severe or repeated vomiting and sudden onset chest pain are two parts of what’s called the Mackler Triad, the trio of signs suggestive of Boerhaave syndrome. Bruce Y. Lee, Forbes.com, 28 June 2025 The findings revealed that residents living closer to these investments — within 0.1 miles — experienced smaller declines in sleep efficiency and smaller increases in wakefulness after sleep onset compared to those living farther away. Wendy Troxel, Baltimore Sun, 26 June 2025 Partly to blame is high inflation, claimed Bankrate, which has increased by about 24% since the onset of the pandemic in 2020. Marco Quiroz-Gutierrez, Fortune, 24 June 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

Cite this Entry

“Onset.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onset. Accessed 8 Jul. 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

Last Updated: - Updated example sentences
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