allergy

American  

[al-er-jee] / ˈæl ər dʒi /

noun

• allergies
  plural

1. an abnormal reaction of the body to a previously encountered allergen introduced by inhalation, ingestion, injection, or skin contact, often manifested by itchy eyes, runny nose, wheezing, skin rash, or diarrhea.

2. hypersensitivity to the reintroduction of an allergen.

3. Informal. a strong dislike or aversion, as toward a person or activity.

   He has an allergy to hard work.

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allergy British  

/ ˈælədʒɪ /

noun

1. a hypersensitivity to a substance that causes the body to react to any contact with that substance. Hay fever is an allergic reaction to pollen

2. informal aversion

   he has an allergy to studying

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allergy Scientific  

/ ăl′ər-jē /

1. An abnormally high immunologic sensitivity to certain stimuli such as drugs, foods, environmental irritants, microorganisms, or physical conditions, such as temperature extremes. These stimuli act as antigens, provoking an immunological response involving the release of inflammatory substances, such as histamine, in the body. Allergies may be innate or acquired in genetically predisposed individuals. Common symptoms include sneezing, itching, and skin rashes, though in some individuals symptoms can be severe.

2. See also anaphylactic shock

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allergy Cultural  

1. A highly sensitive reaction of the body to certain substances, such as pollen, that are present in amounts that do not affect most people. Common indications of allergy include sneezing, skin rashes, itching, and runny nose.

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Other Word Forms

Noun Inflected Forms

• allergies
  plural

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Etymology

Origin of allergy

1910–15; < Greek áll ( os ) other + -ergy < Greek -ergia, equivalent to érg ( on ) activity + -ia -y ³

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Explanation

An allergy is a physical reaction to some specific food or substance. If you have an allergy to cats, they'll make you itchy and swollen no matter how much you love to pet them. If you have an allergy, it can range from mild — itchy eyes in the springtime — to serious — being unable to breathe after eating a peanut. People have allergies to all kinds of things, including milk, chocolate, corn, dust, mold, and just about any kind of animal you can think of. Allergy was originally Allergie, a German word invented by a doctor who combined the Greek roots allos, "other, different, or strange," and ergon, "activity."

Example Sentences

See Examples For:

allergy allergies

The family of a 12-year-old girl who died after drinking a milkshake made in an unwashed blender at a cafe have called for a dedicated rating that scores food businesses on their allergy management.

From BBC ● Oct. 8, 2026

Natasha's Foundation founder Tanya Ednan-Laperouse, whose daughter died aged 15 from an allergy to sesame in a Pret A Manger baguette, said allergies were "a serious, unpredictable medical condition".

From BBC ● Oct. 8, 2026

These sublethal effects can be compared to the way an over-the-counter antihistamine may relieve allergy symptoms while also causing drowsiness.

From Science Daily ● Aug. 6, 2026

Still others described unexplained rashes, outbreaks of diarrhea and infestations of lice, among a host of other maladies for which many said they were offered only Tylenol or allergy medication.

From Los Angeles Times ● Jul. 24, 2026

One Sunday, midway into a film, his mother left for the pharmacy, to buy her allergy medicine.

From "Americanah" by Chimamanda Ngozi Adichie

Protein shakes, powders or bars can be useful for some, including high-level athletes and those who have certain allergies, but they should not replace a healthy diet.

From BBC ● Oct. 15, 2026

It also found nearby restaurants that could deliver food, taking into account any allergies of the attendees.

From The Wall Street Journal ● Oct. 8, 2026

Meanwhile, conditions like allergies often don’t show up until a pet is 2 or 3 years old, Quammen said.

From MarketWatch ● Sep. 15, 2026

But please do not do this if you have allergies, or are likely to get stung.

From Science Daily ● Jul. 29, 2026

The adults exchange phone numbers, and Ms. Sitton asks if I have any allergies.

From "The Miscalculations of Lightning Girl" by Stacy McAnulty

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Related Words

• hay fever

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