n :  an alkaloid C₄₆H₅₆N₄O₁₀ that is obtained from a periwinkle (Catharanthus roseus syn. Vinca rosea) and that is used esp. in the form of its sulfate to treat some human neoplastic diseases (as leukemias and Wilms' tumor) - called also leurocristine  - see ONCOVIN  .
 
 
 
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