Online Medical DictionaryMedTerms™

  1. MedTerms medical dictionary is the medical reference for MedicineNet.com. Our doctors define difficult medical language in easy-to-understand explanations of over 16,000 medical terms.
  2. MedTerms online medical dictionary provides quick access to hard-to-spell and often misspelled medical definitions through an extensive alphabetical listing.

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If you know the spelling, use the search function above to look up the meaning of the medical term in MedTerms and find related medical articles on MedicineNet.com. If you're not sure of the spelling (medical misspellings are common), type the first few letters, followed by an asterisk(*).

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Peanut allergy: An allergic reaction to peanuts, the leading cause of anaphylaxis, the most severe and potentially life threatening allergic reaction, and the leading cause of death from...

Full medical definition for Peanut allergy »
Related Article: Food Allergy main article »


A Note to Healthcare Professionals: The MedTerms online medical dictionary is written with consumers and patients in mind. Here are other medical reference books recommended by our doctors:

  • Dorland's Illustrated Medical Dictionary
  • Mosby's Medical Dictionary
  • Stedman's Medical Dictionary
  • Taber's Cyclopedic Medical Dictionary