allergy

play
noun al·ler·gy \ ˈa-lər-jē \

Definition of allergy

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

Examples of allergy in a Sentence

  1. Many people have some form of allergy.

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

Recent Examples of allergy from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'allergy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of allergy

German Allergie, from all- + Greek ergon work — more at work


ALLERGY Defined for English Language Learners

allergy

play
noun

Definition of allergy for English Language Learners

  • : a medical condition that causes someone to become sick after eating, touching, or breathing something that is harmless to most people


ALLERGY Defined for Kids

allergy

play
noun al·ler·gy \ ˈa-lər-jē \

Definition of allergy for Students

plural allergies
:a condition in which a person is made sick by something that is harmless to most people

Medical Dictionary

allergy

play
noun al·ler·gy \ ˈal-ər-jē \

medical Definition of allergy

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


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