onion

noun

on·​ion ˈən-yən How to pronounce onion (audio)
plural onions
1
: a widely cultivated Asian herbaceous plant (Allium cepa) of the amaryllis family that has a pungent edible bulb and that is closely related to the garlic, chive, and leek
also : its bulb
2
: any of various usually ornamental alliums (such as Allium amplectens or A. caeruleum) related to the onion
oniony
ˈən-yə-nē How to pronounce onion (audio)
adjective
an oniony flavor
oniony meatloaf

Examples of onion in a Sentence

The recipe calls for chopped onions. He is growing onions in the garden this year. The recipe calls for chopped onion.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The sandwich consisted of a marinated skinless chicken breast filet, lettuce, tomato, sweet red onion, Monterey Jack cheese and a herb sauce, all piled on a bun, according to a 1993 press release about the menu item. — Sadie Chafe, FOXNews.com, 21 Oct. 2026 There will also be a pastrami version, and a vegan option made of mushroom and onion. — Stephanie Breijo, Los Angeles Times, 20 Oct. 2026 Place the onion, tomatoes, poblanos, garlic cloves, and serranos on a baking sheet. — ABC News, 20 Oct. 2026 Kumar also points to cane vinegar’s importance in Northern Indian pickling traditions, including sirka pyaaz, tangy onions commonly served alongside kebabs. — Emily Saladino, Bon Appetit Magazine, 19 Oct. 2026 See All Example Sentences for onion

Word History

Etymology

Middle English, from Anglo-French oignon, from Latin union-, unio

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of onion was in the 14th century

Phrases Containing onion

Rhymes for onion

See All Rhymes for onion

Browse Nearby Words

on ice
onion
onion couch
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Cite this Entry

“Onion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onion. Accessed 27 Oct. 2026.

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Kids Definition

onion

noun
on·​ion ˈən-yən How to pronounce onion (audio)
: a widely grown Asian herb related to the lilies and having edible bulbs that have a sharp odor and taste and are used as a vegetable and to season foods
also : its bulb

More from Merriam-Webster on onion

Britannica.com: Encyclopedia article about onion

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