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

• aggression
• assault
• attack
• attempt
• blitz
• blitzkrieg
• charge
• coup de main
• descent
• offense
• offence
• offensive
• onslaught
• raid
• rush
• 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

For example, the American Cancer Society reports that early onset colorectal cancer cases in adults younger than 50 grew by 2.4% each year from 2012-2021. —The Editorial Board, Chicago Tribune, 27 Jan. 2025

But from the onset, the second-oldest republic in the Western Hemisphere after the United States was beset by armed conflict, foreign interventions, repressive dictators, political violence, and heads of state whose personal ambitions and desire for power fanned instability and revolts. —Jacqueline Charles, Miami Herald, 26 Jan. 2025

From the onset, Unkovski introduces a rich soundtrack that mixes modern English-language songs with tracks specific to the region, as well as Alen Sinkauz and Nenad Sinkauz’s larger-than-life score, which sounds as if Ahmet were a mythical paladin on a quest. —Carlos Aguilar, Variety, 25 Jan. 2025

But conditions like an overactive thyroid, menopause, or early onset of a serious infection can, too, Gee says. —Angela Haupt, TIME, 24 Jan. 2025

Word History

First Known Use

circa 1522, in the meaning defined at sense 1

Phrases Containing onset

• adult-onset diabetes
• juvenile-onset diabetes

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