A "corona" is a term that means "crown" in Latin. In astronomy, it refers to the outer atmosphere of a star, including our Sun. The solar corona is visible during a total solar eclipse, appearing as a halo of plasma surrounding the Sun. It is much hotter than the surface of the Sun, with temperatures reaching millions of degrees Celsius. In a different context, "corona" can also refer to a type of dental crown used in dentistry. This is a cap placed over a tooth to restore its shape, size, strength, and appearance. Dental crowns are often made from materials like porcelain, metal, or resin.