There are various synonyms for the term "made vitreous." One such synonym is "glassified." It refers to the process of making something glass-like in texture and appearance. Another synonym is "vitrified," which means transformed into or resembling glass through heating and fusion. "Fused" is another term used to describe the process of making something vitreous. It refers to the process of melting and blending two materials together to form a single, solid substance. "Molten" describes something that has been liquefied by heat and fused together to create a more solid form. Overall, these synonyms all describe the process of creating a glass-like substance from various materials.