What Is a Pap Smear? Cancer of the cervix (cervical cancer) is the fourth most common cause of cancer-related death among women worldwide. The best way to detect cervical cancer is by having regular Papanicolaou tests, or Pap smears. (Pap is a shortened version of the name of the doctor who developed the screening test). A Pap smear is a microscopic examination of cells taken from the uterine cervix.