onset

noun

on·​set ˈȯn-ˌset 

ˈän-

1

: attack, assault

withstand the onset of the army

2

: beginning, commencement

the onset of winter

the onset of age-related diseases

Synonyms of onset

• attack
• assault
• onslaught
• raid
• offensive
• aggression
• offense
• strike

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 organization’s website states that receiving CPR immediately after the onset can help to double – even triple – the chances of surviving. —Pioneer Press, Chicago Tribune, 5 Feb. 2026

Take time now to fasten or shelter loose objects in a safe location prior to the onset of high winds. —Nc Weather Bot, Charlotte Observer, 5 Feb. 2026

Boring Company’s president, Steve Davis, had called the Governor’s Office about the citations and set up that meeting, and the citations were rescinded at the onset of the meeting. —Jessica Mathews, Fortune, 5 Feb. 2026

Initially, the onset is usually marked by workers or unemployed, dissatisfied, striking and/or disaffected rioters in the streets. —Voice Of The People, New York Daily News, 3 Feb. 2026

Word History

First Known Use

circa 1522, in the meaning defined at sense 1

Phrases Containing onset

• adult-onset diabetes
• juvenile-onset diabetes

Rhymes for onset

• abet
• asset
• baguette
• banquette
• barbette
• beget
• beset
• brevet
• briquette
• brunet
• brunette
• burette

Kids Definition

onset

noun

on·​set ˈȯn-ˌset 

ˈän-

1

: attack entry 2 sense 1

2

: beginning sense 1

Medical Definition

onset

noun

on·​set ˈȯn-ˌset, ˈän- 

: the initial existence or symptoms of a disease

the onset of scarlet fever