2
: beginning, commencement
the onset of winter
the onset of age-related diseases
Synonyms
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
Climate Denial as a Defense Mechanism Much like a terror management lab experiment – or the onset of the COVID-19 pandemic– natural disasters like hurricanes Helene and Milton trigger death anxiety.
—
Discover Magazine, 8 Nov. 2024
As a longtime Palo Alto resident, she’s been to the gardens throughout her life, and recalls stopping by for a visit in 2020 just before widespread shelter-in-place orders went into effect with the onset of the COVID-19 pandemic.
—Isha Trivedi, The Mercury News, 5 Nov. 2024
Moscow has had success in the past on this front, however, notably playing a significant part in mending their ties with Damascus, which returned to the Arab League last year after being shut out at the onset of the civil war in 2011.
—Gordon G. Chang, Newsweek, 31 Oct. 2024
James and her fellow attorneys general noted that price gouging was especially prevalent at the onset of the Ukraine war and during the COVID-19 pandemic, both of which were issues that affected the national supply chain.
—Sarah Fortinsky, The Hill, 30 Oct. 2024
See all Example Sentences for onset 
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Discover Magazine, 8 Nov. 2024
As a longtime Palo Alto resident, she’s been to the gardens throughout her life, and recalls stopping by for a visit in 2020 just before widespread shelter-in-place orders went into effect with the onset of the COVID-19 pandemic.
—Isha Trivedi, The Mercury News, 5 Nov. 2024
Moscow has had success in the past on this front, however, notably playing a significant part in mending their ties with Damascus, which returned to the Arab League last year after being shut out at the onset of the civil war in 2011.
—Gordon G. Chang, Newsweek, 31 Oct. 2024
James and her fellow attorneys general noted that price gouging was especially prevalent at the onset of the Ukraine war and during the COVID-19 pandemic, both of which were issues that affected the national supply chain.
—Sarah Fortinsky, The Hill, 30 Oct. 2024
See all Example Sentences for onset
Dictionary Entries Near onset
Cite this Entry
“Onset.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onset. Accessed 22 Nov. 2024.
Copy CitationKids Definition
onset
noun
on·set
ˈȯn-ˌset 
ˈän-
Medical Definition
onset
noun
on·set
ˈȯn-ˌset, ˈän-
: the initial existence or symptoms of a disease
the onset of scarlet fever
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