Do-rag
A do-rag (also known as a doo-rag, du-rag, or durag), is a piece of cloth used to cover the top of one's head. Sometimes made of nylon material and having a "skullcap" fit it may also be referred to as a "wavecap". According to the Oxford English Dictionary and Merriam-Webster dictionary, the term derives from 'do as in hairdo.
Read more about Do-rag.