allergy

noun

al·​ler·​gy ˈa-lər-jē 

plural allergies

1

: altered bodily reactivity (such as hypersensitivity) to an antigen in response to a first exposure

a bee venom allergy so severe that a second sting may be fatal

2

: exaggerated or pathological immunological reaction (as by sneezing, difficult breathing, itching, or skin rashes) to substances, situations, or physical states that are without comparable effect on the average individual

3

: medical practice concerned with allergies

4

: a feeling of antipathy or aversion

Synonyms

• averseness
• aversion
• disfavor
• disinclination
• dislike
• disliking
• disrelish
• down [chiefly British]
• mislike

Examples of allergy in a Sentence

Many people have some form of allergy.

independent-minded people who seem to have an allergy to any control from the government

Recent Examples on the Web

There are also more aggressive interventions for people with severe allergies who don’t respond to other medicines like desensitization therapy, also known as allergy shots. —Umair Irfan, Wired News, 5 Apr. 2025

These allergens must be clearly identified on food labels as the failure to do so could pose a serious health risk to individuals with allergies. —Newsweek Staff, MSNBC Newsweek, 4 Apr. 2025

Think about the drastic rise in food allergies among children in the U.S., which has more than doubled in prevalence since the 1990s. —Aram Sinnreich and Jesse Gilbert, Time, 3 Apr. 2025

Mather said that some people who have developed this allergy from a lone star tick bite have had conditions from gastric distress to spots on their skin to, in the most severe situations, anaphylaxis from eating red meat. —Margie Cullen, USA Today, 1 Apr. 2025

Word History

Etymology

borrowed from German Allergie "heightened reaction to an antigen to which an individual has been previously exposed," from all- all- + -ergie, in Energie energy, or directly from its source, Greek -ergeia, taken to mean "action, response"

Note: The term was introduced, along with allergisch allergic and Allergen allergen, by the German physician Clemens Peter Freiherr von Pirquet (1874-1929) in "Allergie," Münchener medizinische Wochenschrift, 53. Jahrgang, Nr. 30 (July 24, 1906), pp. 1457-58.

First Known Use

1908, in the meaning defined at sense 1

Phrases Containing allergy

• allergy shot
• anti-allergy

Kids Definition

allergy

noun

al·​ler·​gy ˈal-ər-jē 

plural allergies

1

: exaggerated or abnormal reaction (as by sneezing, itching, or rashes) to substances, situations, or physical states that do not have such a strong effect on most people

2

: a feeling of dislike

Medical Definition

allergy

noun

al·​ler·​gy ˈal-ər-jē 

plural allergies

1

: altered bodily reactivity (as hypersensitivity) to an antigen in response to a first exposure

his bee-venom allergy may render a second sting fatal

2

: exaggerated or pathological reaction (as by sneezing, respiratory embarrassment, itching, or skin rashes) to substances, situations, or physical states that are without comparable effect on the average individual

3

: medical practice concerned with allergies