chrysoberyl UK /ˈkɹɪs.ə(ʊ)ˌbɛɹ.ɪl/US /ˈkɹɪs.əˌbɛɹ.əl/ noun1 •A vitreous mineral, often pale green, a mixed oxide of aluminium and beryllium with the chemical formula BeAl₂O₄, used as a gemstone. formschrysoberyls