A derogatory term for one who rides a Harley Davidson (or other cruiser style motorcycle). Hanky denotes the black bandana they are wearing on their head. This is worn in addition to their leather ass-less chaps, blackboots, and denim vest. This is their idea of promoting they are bad asses (lol).
Look at that hanky head and his trashybroad. She looks used and abused and has sugar glider wings as tricep muscles.