mendelevium(n = noun.substance)atomic number 101, md, mv - a radioactive transuranic element synthesized by bombarding einsteinium with alpha particles (Md is the current symbol for mendelevium but Mv was formerly the symbol);
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. [PJC]