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

TJ’s knows that you can’t have turkey without gravy on the side, hence why they offer a “ready-to-use” Turkey Gravy seasoned with herbs, onion powder, garlic powder, turmeric extract and dried potato flakes.

From Salon

There isn’t a seafood counter, and a small “Georgia Grown” section offered mostly potatoes, onions and peanuts, though it will carry more items in the summer months.

From The Wall Street Journal

"We work hard to include vegetables like sweet peppers, onion and potatoes. This enables us to improve the taste and the nutritional value."

From BBC

There’s a rhythm to it, a small, absorbing joy in watching butter brown, garlic bloom, onions soften.

From Salon

Burgundy wine, beef demi-glace, sage and thyme complement the sweetness of the onions in this rich gravy.

From The Wall Street Journal