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 of allergy

• dislike
• hatred
• disliking
• distaste

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

Get Ahead of the Next Pollen Wave Timing is everything with allergy medication. —Allison Palmer, Sacbee.com, 22 Apr. 2026

Once or twice daily during allergy season is the right frequency; daily use year-round can deplete the nose’s natural immune defenses. —Allison Palmer, Fort Worth Star-Telegram, 22 Apr. 2026

Sibling age gaps of less than four years were associated with a lower rate of allergies and asthma—likely because kids who are closer in age interact more often, sharing germs that improve their microbiome. —Sara Novak, Scientific American, 21 Apr. 2026

Some individuals may have sensitivities or allergies, Ramping says, but it's generally considered safe when used appropriately. —Randi Gollin, Martha Stewart, 17 Apr. 2026

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