From The Food Encyclopedia by Jacques Rolland and Carol Sherman
A fatty spread made by churning cream until it reaches a semisolid state. The origin of the name is a combination of the Greek bous, or "cow", and turos, "cheese." The origin of butter goes back to the earliest nomadic people, who used to churn the milk of the cows, goats, ewes, asses, mares and camels that were following them in their wanderings. The Aryans brought the knowledge of butter to India, where it soon became a sacred food. In Indian mythology, the Salmala is a river of butter that winds about the world. (For Butter Grades see below.)
