The term 'Hole in Your Head' can be broken down into three crossword solutions: SINUS (5 letters), PORE (4 letters), and NOSTRIL (7 letters). A SINUS is a cavity in the skull that is filled with air and connected to the nasal cavity. Pores are small openings in the skin that secrete sweat and oil. Nostrils are the two openings in the nose that allow air to enter the body. Together, these three solutions form the phrase 'Hole in Your Head, ' which refers to the many openings in the head that allow air to enter the body.