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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Avian influenza: A highly contagious viral disease with up to 100 percent mortality in domestic fowl. Caused by influenza A virus subtypes H5 and H7. All types of...

Full medical definition for Avian influenza »
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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