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allergy

play
noun al·ler·gy \ˈa-lər-jē\

Simple Definition of allergy

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of allergy

plural

allergies

  1. 1 :  altered bodily reactivity (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. 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. 3 :  medical practice concerned with allergies

  4. 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>



Origin and Etymology of allergy

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


First Known Use: 1910


ALLERGY Defined for Kids

allergy

play
noun al·ler·gy \ˈa-lər-jē\

Definition of allergy for Students

plural

allergies

  1. :  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. 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. 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. 3:  medical practice concerned with allergies





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