Viosterol is a term for a form of Vitamin D that is used for medical purposes. This nutrient is essential for maintaining healthy bones and teeth, as well as supporting the immune system and regulating mood. While viosterol is the specific term for this type of Vitamin D, there are several other synonyms that can be used to refer to it. Some of the commonly used synonyms for viosterol include ergocalciferol, calciferol, and cholecalciferol. Each of these terms refers to the same type of Vitamin D and can be used interchangeably depending on the context in which they are being used.