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An inflammatory disease caused by a spirochete (Borrelia burgdorferi) that is transmitted by ticks and usually characterized by an initial rash followed by flulike symptoms including fever, joint pain, and headache. If left untreated, the disease can result in chronic arthritis and nerve and heart dysfunction.
[AfterLymeand OldLyme, towns in southeast Connecticut where the diagnosis of an unusually high number of juvenile arthritis cases in 1975 led to the identification of the disease.]
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.