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

When I finally nailed a roast chicken — buttered and oiled, stuffed with lemon wedges and hunks of onion and fennel — I felt like a goddess.

From Salon

The company, Irvine-based Ventura Foods, recalled 3,556 cases of the dressing that could be contaminated by “black plastic planting material” in the granulated onion used, according to an alert issued by the U.S.

From Los Angeles Times

The report specified that the “foreign objects” in question are black plastic planting material found in granulated onion used to make the dressing.

From Salon

Another pasta, this time a chicken spaghetti smells like Sunday afternoons in the South: sweet onions softening in olive oil, bell peppers and celery faintly caramelizing, mushrooms releasing their earthy perfume.

From Salon

Thin-sliced celery or carrots, fennel shaved translucent, a few slivers of red onion or scallions, even cucumbers if you’re craving something clean and cold.

From Salon