The term 'hammerhead feature' refers to two distinct parts of a hammer. The first part is the CLAW, which is the curved metal piece at the top of the hammer that is used to pull out nails. The second part is the peen, which is the flat end of the hammer head that is used to drive nails into wood. Both the CLAW and the peen are essential components of a hammer and are necessary for it to function properly.