Whorl
A spot where hair grows outwards in a spiral, usually at the crown, sometimes two of them.
Also: hair whorl, double crown
A whorl is a circular patch where hair grows out in a spiral, clockwise or anticlockwise. Most people have one near the crown, and some have two, called a double crown. Because the hair at a whorl points in every direction, it can make a gap or a tuft in short hair. Barbers find it before they cut and leave enough weight there to hold it down, or use it as the natural point for a parting.