2. (noun)molybdenum, Mo, atomic number 42 a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel Synonyms: second, atomic number 42, molybdenum, bit, moment, minute
3. (noun)Missouri, Show Me State, MO a midwestern state in central United States; a border state during the American Civil War, Missouri was admitted to the Confederacy without actually seceding from the Union Synonyms: second, molybdenum, bit, moment, minute, atomic number 42