The term atopy was coined by Coca and Cooke in 1923.[5][2] Many physicians and scientists use the term "atopy" for any IgE-mediated reaction (even those that are appropriate and proportional to the antigen), but many pediatricians reserve the word "atopy" for a genetically mediated predisposition to an excessive IgE reaction.[3] The term is from Greek ἀτοπία meaning "the state of being out of place", "absurdity".