yttrium Syllabification: (yt·tri·um)Pronunciation: /ˈitrēəm/Definition of yttrium noun the chemical element of atomic number 39, a grayish-white metal generally included among the rare-earth elements. (Symbol: Y)Origin: early 19th century: modern Latin, from Ytterby (see ytterbium)yttrium in other Oxford dictionaries Definition of yttrium in the British & World English dictionary
