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

At Larkin, Williams was diagnosed not with worsening dementia but with schizophrenia, whose onset usually occurs in the late teens or early 20s. —Carol Marbin Miller, Miami Herald, 2 Apr. 2026

Earlier, Lucknow struggled from the onset against the pace of Mukesh Kumar (0-17) in the power play while Lungi Ngidi (3-27) and Natarajan (3-29) intelligently varied their pace. —ABC News, 1 Apr. 2026

Frankenburg has seen commercial conversations with Gulf states speed up since the onset of the Iran war, CEO Kusti Salm told CNBC. —Kai Nicol-Schwarz, CNBC, 31 Mar. 2026

Roughly 90% of these tumors are diagnosed in patients under 20 years old, often around the onset of puberty, making Tamura an outlier. —Rachel Hale, USA Today, 31 Mar. 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