ˈrēnēəm noun
( -s )
Etymology: New Latin, from Latin Rhenus Rhine river + New Latin -ium
: a rare heavy polyvalent metallic element that resembles manganese chemically, that occurs especially in molybdenite, gadolinite, columbite, or platinum ores, that is obtained either as a black or grayish powder by ignition in hydrogen usually of a perrhenate or as a silver-white hard metal (as by sintering the powder), and that is usually used in catalysts for dehydrogenation and in thermocouples — symbol Re ; see element table