yttrium/ˈɪtɹiːəm/EtymologyFrom Ytterby + -ium, named after Ytterby, Sweden, the same etymological source as terbium, erbium, and ytterbium.yttrium means A silvery metallic chemical element with an atomic number of 39, mainly found in combination with lanthanide elements in rare earth minerals. Lexicurio rates it Rare gem — a strength score of 81 out of 100.nounA silvery metallic chemical element with an atomic number of 39, mainly found in combination with lanthanide elements in rare earth minerals.