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 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.
Bulbing onions are usually too demanding for indoor gardens, but green onions are just the right size for indoor growing. Lauren Landers, Better Homes & Gardens, 28 Dec. 2025 One of my go-to meals is a tofu stir-fry with peppers and onions served over brown rice. Hannah Harper, Health, 27 Dec. 2025 Sweet carrots and onions soften into the broth, while pepperoncini add a bright, tangy kick that lifts the hearty flavors. Kimberly Holland, Southern Living, 26 Dec. 2025 López reportedly found flecks of gold while digging wild onions, sparking an early gold rush. Don Sweeney, Sacbee.com, 26 Dec. 2025 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

Browse Nearby Words

Cite this Entry

“Onion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onion. Accessed 31 Dec. 2025.

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

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