Taphophobia

Fear of being buried alive is the fear of being placed in a grave while still alive as a result of being incorrectly pronounced dead. The abnormal, psychopathological version of this fear is referred to as taphophobia (from Greek τάφος - taphos, "grave, tomb" and φόβος - phobos, "fear"), which is translated as "fear of graves".

Before the advent of modern medicine, the fear was not entirely irrational. Throughout history, there have been numerous cases of people being buried alive by accident. In 1905, the English reformer William Tebb collected accounts of premature burial. He found 219 cases of near live burial, 149 actual live burials, 10 cases of live dissection and 2 cases of awakening while being embalmed.

The 18th century had seen the development of mouth-to-mouth resuscitation and crude defibrillation techniques to revive persons considered dead, and the Royal Humane Society had been formed as the Society for the Recovery of Persons Apparently Drowned. In 1896, an American funeral director, T.M. Montgomery, reported that "nearly 2% of those exhumed were no doubt victims of suspended animation," although folklorist Paul Barber has argued that the incidence of burial alive has been overestimated, and that the normal effects of decomposition are mistaken for signs of life.

There have been many urban legends of people being accidentally buried alive. Legends included elements such as someone entering into the state of sopor or coma, only to wake up years later and die a horrible death. Other legends tell of coffins opened to find a corpse with a long beard or corpses with the hands raised and palms turned upward. Of note is a legend about the premature burial of Ann Hill Carter Lee, the wife of Henry Lee III. On his deathbed in 1799, George Washington made his attendants promise not to bury him for two days.

Literature found fertile ground in exploring the natural fear of being buried alive. One of Edgar Allan Poe's horror stories, "The Premature Burial", is about a person suffering from taphophobia. Other Poe stories about premature burial are "The Fall of the House of Usher" and "The Cask of Amontillado"—and to a lesser extent, “The Black Cat”.

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Wikipedia