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

Symptom timing and onset also vary. —Allison Forsyth, Health, 15 Apr. 2026

Only five Gallup readings have ever come in lower, all of which were recorded during the Great Recession or at the onset of the pandemic. —Nick Lichtenberg, Fortune, 14 Apr. 2026

The study identified type 2 diabetes as the leading cause of death associated with early-onset obesity. —Khloe Quill, FOXNews.com, 14 Apr. 2026

Scars still exist from the Napster days and how unequipped the record labels were to handle the massive scale piracy from peer-to-peer filesharing sites, which cratered music’s value until the onset of the streaming era finally stopped the bleeding. —Ethan Millman, HollywoodReporter, 14 Apr. 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