Hank
A hank is yarn wound into a loose, circular bundle rather than a solid ball, and must be wound with a swift and ball winder before use.
Explanation
A hank is a loose, circular bundle of yarn, usually twisted and tied at a couple of points to hold its shape during transport and sale. Unlike a ready-to-use ball, you cannot knit directly from a hank without the yarn tangling, so it must first be wound, typically using a yarn swift to hold the hank stretched out while a ball winder rolls the yarn into a loose ball. Hand-dyed and specialty yarns are often sold as hanks, since the dyeing process is easier to perform on yarn in this form.