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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Parkinson disease: A slowly progressive neurologic disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with...

Full medical definition for Parkinson disease »
Related Article: Parkinson's Disease 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