on·​ion | \ˈən-yən \

Definition of onion 

1 : a widely cultivated Asian herb (Allium cepa) of the lily family with pungent edible bulbs also : its bulb

2 : any of various plants of the same genus as the onion

Keep scrolling for more

Other Words from onion

oniony \ˈən-​yə-​nē \ adjective

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.
See More

Recent Examples on the Web

Add green peppers and dried chiles and continue to cook until onion is translucent, about 4 minutes. 2. Kitty Greenwald, WSJ, "The Most Warming Winter Stew," 16 Nov. 2018 Stir in the vinegar and sugar, reduce the heat to medium low and cook until the onions are soft and the syrup is sticky, 10 minutes. Joe Yonan, The Seattle Times, "Vegetarian (or vegan) guests for Thanksgiving? Serve them this beauty," 13 Nov. 2018 Cook, stirring occasionally, until onion is soft, 8 to 10 minutes. Anna Helm Baxter, Country Living, "Savory Pumpkin Soup with Spice Shake," 30 Oct. 2018 Saute until the shrimp are done and the onions are translucent. Susan Selasky, Detroit Free Press, "Potato, shrimp and chorizo hash is a spicy delight," 20 May 2018 Rodriguez says: French onion is my favorite soup and this was like biting into a bowl of soup with a burger. cleveland.com, "How about a homemade bakery bun to go with your burger at Creekside Restaurant? Cleveland's Best Burger contest," 10 May 2018 Unfortunately, ornamental onions are subject to the same diseases as edible ones, and so are included in the quarantine. Margaret Lauterbach, idahostatesman, "Check on the health of your rose bushes and climbers | Idaho Statesman," 4 Apr. 2018 No mustard, no pickles, no onion are part of the standard Shake Shack package. Alison Cook, Houston Chronicle, "Burger Friday: Shake Shack," 30 Mar. 2018 In a large bowl, toss sweet potato and onion with oil, rosemary, and ¼ tsp each salt and pepper. Woman's Day Kitchen, Woman's Day, "Apple, Sweet Potato, and Rosemary Flatbread," 9 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'onion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of onion

14th century, in the meaning defined at sense 1

History and Etymology for onion

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

Keep scrolling for more

Learn More about onion

Statistics for onion

Last Updated

28 Nov 2018

Look-up Popularity

Time Traveler for onion

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

See more words from the same century

Keep scrolling for more

More Definitions for onion



English Language Learners Definition of onion

: a round vegetable that is usually white, yellow, or red and has a strong smell and taste


on·​ion | \ˈən-yən \

Kids Definition of onion

: the roundish edible bulb of a plant related to the lily that has a sharp odor and taste and is used as a vegetable and to season foods

Keep scrolling for more

More from Merriam-Webster on onion

Rhyming Dictionary: Words that rhyme with onion

Spanish Central: Translation of onion

Nglish: Translation of onion for Spanish Speakers

Britannica English: Translation of onion for Arabic Speakers

Britannica.com: Encyclopedia article about onion

Comments on onion

What made you want to look up onion? Please tell us where you read or heard it (including the quote, if possible).


amusing and light sparring with words

Get Word of the Day daily email!

Test Your Vocabulary

Late Autumn 2018 Words of the Day Quiz

  • frosted-autumn-leaves
  • Which is a synonym of yahoo?
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!