The term 'Mass of Hair' can be described by two crossword solutions: 'shag' and 'MOP'. 'Shag' is a four-letter word that refers to a hairstyle characterized by long, layered hair. It is often associated with the 1970s and is still popular today. 'MOP' is a three-letter word that refers to a hairstyle characterized by thick, long hair that is usually parted in the middle. This style was popularized in the 1950s and is still seen today. Both of these styles involve a large mass of hair.