What is a white crystalline substance related to the glycols, and made from acetone; hence, by extension, any one of a series of substances of which pinacone proper is the type. [Written also pinakone.] called?

pinacone — A white crystalline substance related to the glycols, and made from acetone; hence, by extension, any one of a series of substances of which pinacone proper is the type. [Written also pinakone.]. (Webster's 1913.)