Dictionary.com Word FAQs
Where can I find names of diseases?
Sites like that of the Mayo Clinic or the Department of Health and Human Services' Centers for Disease Control and Prevention are the best. There are others, like Karolinska Institutet Alphabetic List of Specific Diseases/Disorders that may be helpful, also. A site of medical eponyms - medical phenomena named for persons - is http://www.whonamedit.com/.