What nickname is sometimes given to the ball used in American football?

In Canada and the United States, a football (also called a pigskin) is a ball, roughly in the form of a prolate spheroid, used in the context of playing gridiron football. Footballs are often made of cowhide leather, as such a material is required in professional and collegiate football. Footballs used in recreation, and in organized youth leagues, may be made of rubber, plastic or composite leather (high school football rule books still allow inexpensive all-rubber footballs, though they are less common than leather).

In the 1860s, manufactured inflatable balls were introduced through the innovations of English shoemaker Richard Lindon. These were much more regular in shape than the handmade balls of earlier times, making kicking and carrying easier. These early footballs were plum-shaped.