onion

American  

[uhn-yuhn] / ˈʌn yən /

noun

1. a plant, Allium cepa, of the amaryllis family, having an edible, succulent, pungent bulb.

2. any of certain similar plants.

3. the bulb of the onion plant.

4. the flavor or odor of this bulb.

5. Slang. a person.

   He's a tough onion.

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adjective

1. containing or cooked with onions.

   onion soup.

2. of, relating to, or resembling an onion.

idioms

1. know one's onions, to know one's subject or business thoroughly; be capable or proficient.

onion British  

/ ˈʌnjən /

noun

1. an alliaceous plant, Allium cepa, having greenish-white flowers: cultivated for its rounded edible bulb

2. the bulb of this plant, consisting of concentric layers of white succulent leaf bases with a pungent odour and taste

3. any of several related plants similar to A. cepa, such as A. fistulosum (Welsh onion)

4. slang to be fully acquainted with a subject

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onion More Idioms  

1. see know one's stuff (onions).

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Other Word Forms

• onionlike adjective
• oniony adjective

Etymology

Origin of onion

1325–75; Middle English onyon < Old French oignon < Latin ūniōn- (stem of ūniō ) a unity, large pearl, onion; union

Example Sentences

In addition to French green lentils, you’ll need a medium yellow onion, carrots, garlic, bay leaf, vegetable broth, diced cooked ham, olive oil, cracked black pepper, sea salt and za’atar.

From Salon

French onion soup can make for an easy, cozy dinner party.

From The Wall Street Journal

Henk de Haan, 63, throws onions and carrots into a pan -- essential ingredients in snert, a thick soup made with winter vegetables and pork, typically finished off with slices of Dutch smoked sausage.

From Barron's

Each week, during the British winter, it supplies two million bunches of spring onions, 100 tonnes of green beans and 80 tonnes of radishes.

From BBC

I could practically hear my female ancestors whispering, Just go chop the onions.

From Salon