Yttrium, a metallic element with the symbol Y and atomic number 39, has numerous synonyms that are used to describe it. Some of the common synonyms include ytterbium, yttria, scandium, and cerium, which are related to different aspects of yttrium. While ytterbium is similar to yttrium in terms of physical and chemical properties, yttria refers to the oxide of yttrium. Likewise, scandium and cerium are also related to yttrium in terms of their properties, compositions, and uses. These synonyms are often used interchangeably to describe and classify different elements, compounds, and materials related to yttrium.