GNU Collaborative International Dictionary of English

Found one definition

1.       
   mendelevium (mĕn‑dĕ‑lēˈvē‑ŭ/m), a. [From Dmitri Mendeleyev, discoverer of the periodic law.] (Chem.) an unstable radioactive element discovered in 1955 and produced artificially only in very small quantities; symbol Md (also Mv).  It is a transuranic element with atomic number 101.  Isotopes 255, 256, 257, and 258 have been prepared.  Md258, the longest-lived, has a half-life of two months.  HCP61
   
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