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 tremor led to a consultation with a neurologist and the devastating diagnosis of early-onset Parkinson’s. —Stephanie Nolasco, FOXNews.com, 17 Nov. 2025

Moscow is intensifying its strikes against critical infrastructure -- particularly energy targets -- all across Ukraine coinciding with the onset of wintry weather, according to Ukrainian officials. —David Brennan, ABC News, 16 Nov. 2025

Research also shows that runners who regularly engaged in cold immersion therapy reported less delayed onset muscle soreness (DOMS) than those who simply rested. —Laura Scholz, Outside, 16 Nov. 2025

Young members passed this milestone at puberty, and the average age of puberty onset in the community seems to have been 13. —Jane Borden, Rolling Stone, 15 Nov. 2025

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