However, you could use these options depending on the context:
* A bale of wool: This is the most common and practical way to refer to a large quantity of wool.
* A fleece of wool: This refers to the wool from a single sheep.
* A pile of wool: This is a simple and general way to describe a collection of wool.
* A wad of wool: This implies a smaller, more compact quantity of wool.
You could also get creative and invent your own collective noun for wool, like "a fluff of wool" or "a cloud of wool".