Any of a group of antibiotics originally isolated from a strain of the soil microorganism Streptomyces mediterranei, used in the United States to treat tuberculosis and prevent meningococcal infections, and used in other countries to treat leprosy and other bacterial diseases.
[Alteration (perhaps influenced by A(MINO-)) of earlier rifomycin : Rififi, alternate title of Du rififi chez les hommes, a 1955 French film noir that was a favorite of the researchers who first isolated rifamycins and who used film titles as nicknames for new compounds before formal publication of their results (from French slang rififi, scuffle, gang rumble, from reduplication of rif, fire, gunfire, combat, from Italian slang ruffo, fire, from dialectal Italian ruffo, red-headed, from Latin rūfus, reddish, red-headed; see reudh in the Appendix of Indo-European roots) + -MYCIN.]
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Indo-European & Semitic Roots Appendices
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.