The word "coccyx" refers to the small bone located at the bottom of our spine, also known as the tailbone. It is the remnant of a tail that our ancestors had long ago. Full definition
Pelvic pain experienced over the tailbone or coccyx which usually worsens with prolonged sitting. (proactiveph.com)
The Ziraki Coccyx Seat Cushion features thick 2.8» memory foam padding with a velvety soft velour cover. (geekwrapped.com)
$ 5,000: Fracture of the skull (dome of the skull), spine (including coccyx), pelvis or femur $ 1,500: Fracture of a rib or the sternum, scapula, humerus, patella, tibia or fibula $ 750: Fracture of a bone not listed above (statefarm.ca)