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

According to the report, both men fell ill after spending time outdoors, one playing golf at five courses in Alameda and Contra Costa counties within 14 days of the onset of his symptoms. —Karen Garcia, Los Angeles Times, 16 June 2026

She was cut during training camp From the onset of training camp, Dastrup impressed Finglass and Trammell with her showmanship. —Lynsey Eidell, PEOPLE, 16 June 2026

For others, the onset of a serious condition — a stage when steady care is crucial — could complicate their ability to work consistently. —Lisa Jarvis, Mercury News, 16 June 2026

In November, 2023, after Hamas’s massacre of Israelis and the onset of Israel’s brutal counterstrike on Gaza, Habermas signed a statement that reasserted solidarity between Germany and Israel. —Alex Ross, New Yorker, 15 June 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
• binet
• 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