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.
Making moves after learning is just as critical as learning from the onset. Fnu Anupama, Forbes.com, 10 June 2025 Alex’s attorney, Jim Griffin, revealed that the grieving husband and father was considered a person of interest from the onset of the authorities’ investigation into the murders. Lynsey Eidell, People.com, 7 June 2025 Coming midseason are Fox’s Doc Martin remake Best Medicine and Memories of a Killer, in which a hitman develops early onset Alzheimer’s. Jesse Whittock, Deadline, 5 June 2025 Taking that into account from the onset, the filmmaker and creator first works to gain the trust of his subjects and search for the truth, and then find ways to express that by working in partnership with them. Chris O'Falt, IndieWire, 3 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 13 Jun. 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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