Wool fibers are hygroscopic, meaning they readily absorb moisture, and are hollow. Because wool ignites at a higher temperature than cotton and other fibers, and is self-extinguishing, it is often used in firefighters uniforms and in other environments where safety from fire is concerned.
Curiously, but perhaps not entirely surprising, it's also traditionally been used as a cover for cloth diapers. The exterior of wool fibers are hydrophobic (water repellent) and the interior of it is hygroscopic (water absorbent). This keeps the moisture inside diapers rather than anywhere else. Wool that has been felted and treated with lanolin is slightly antibacterial, air permeable, and hydrophobic, all good things for those in diapers, and for those of us who deal with small persons in diapers.
But of course, our favorite use for wool is seasonal outerwear. Check out a couple of our favorites here:
In another thought, your new word of the week is now hygroscopic. If anyone manages to work this word naturally into conversation, please let us know in the comments.