What is a synonym for ball of yarn?

General:

* Skein

* Hank

* Clew

* Coil

* Tangle

More descriptive:

* Yarn ball

* Yarn skein

* Yarn hank

* Wound yarn

* Knitter's delight

Informal:

* Yarn wad

* Yarn blob

* Yarn pile

The best synonym will depend on the context of your writing.