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 team decided not to commit to a set number of scans at the onset, and took it day by day to see how much the grad student could handle. — Mack Degeurin, Popular Science, 9 Sep. 2026

The findings offer new insight into the factors behind early-onset cases. — Gina Park, CNN Money, 9 Sep. 2026

While the geological events would occur anyway, one problem is that the onset of the super El Nino phenomenon is setting off more risks of extreme weather worldwide. — Justina Lee, CNBC, 8 Sep. 2026

The American College of Obstetricians & Gynecologists says people can wait a decade or more after the onset of symptoms to receive a diagnosis of endometriosis. — Laura Ungar, Los Angeles Times, 8 Sep. 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