onset
Americannoun
-
a beginning or start.
the onset of winter.
-
an assault or attack.
an onset of the enemy.
-
Phonetics. the segment of a syllable preceding the nucleus, as the gr in great.
noun
-
an attack; assault
-
a start; beginning
Etymology
Origin of onset
Compare meaning
How does onset compare to similar and commonly confused words? Explore the most common comparisons:
Explanation
When something is at its onset, it's at the beginning, just getting started, and it's often something that's not so pleasant. The onset of hurricane season is probably not the best time to visit the beach. If you catch an infection right at the onset and treat it immediately, the infection may not last so long. You can also have an early onset of something, and that usually means something you'd rather not have at all, as with early-onset Alzheimer's, a disease that usually appears after age 65. If you begin showing signs of the disease at a younger age than usual, you're said to have early-onset Alzheimer's.
Vocabulary lists containing onset
The Vocabulary.com Top 1000
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
ACT Vocabulary List
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
The Crossover
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Many oil-market analysts at the onset of the U.S.-Iran war said the global economy would start to feel the pinch of a virtually shut Strait of Hormuz as early as May.
From MarketWatch • May 26, 2026
One form of the protein, APOE4, is considered the greatest genetic risk factor for late onset Alzheimer's disease.
From Science Daily • May 20, 2026
Plus, natural-gas prices surged in Europe and Asia but barely rose in the U.S., a price divergence that has saved U.S. consumers trillions since the onset of the shale revolution.
From The Wall Street Journal • May 16, 2026
The Dome closed in March 2020 with the onset of the COVID-19 pandemic and in April 2021 it was announced that the venue would not be reopening.
From Los Angeles Times • May 12, 2026
The headaches did not bother her as much as the sudden onset of that deep trancelike sleep which still occurred without warning.
From "Harriet Tubman: Conductor on the Underground Railroad" by Ann Petry
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
