onion

noun

on·​ion ˈən-yən 

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 

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

Cooked low and slow over oak or mesquite, brisket is sliced thick and served with minimal fuss—just a few pickles, onions, and a slice of white bread. —Staff Report, Hartford Courant, 3 Aug. 2025

They are filled with onions, carrots, and potatoes, and spicy green garlic sauce. —Ronny Maye, Forbes.com, 31 July 2025

McDonald's recently added a new burger to the Value Menu—the Daily Double burger, which comes with two beef patties, American cheese, shredded lettuce, slivered onions, mayo and tomato. —Thomas Westerholm, MSNBC Newsweek, 31 July 2025

The Depression-era novelty was invented at the bygone Hamburger Inn as a means of stretching pricey ground beef by smashing it with slivered onions. —Matt Kirouac, AFAR Media, 31 July 2025

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

Phrases Containing onion

• Bermuda onion
• green onion
• onion dome
• onion ring
• pearl onion
• sea onion
• Spanish onion
• spring onion

Rhymes for onion

• trunnion

Kids Definition

onion

noun

on·​ion ˈən-yən 

: 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