ABetelgeuse. It's the name of a star in the Orion constellation, from the Arabic Bet al-Jauza', "armpit of the central one." The spelling of the film's name is phonetic.
ALooking for a project to make after the success of "Pee Wee's Big Adventure," Burton optioned a script by horror author Michael McDowell. Being a horror author, McDowell's script was decidedly non-comedic, and was primarily a horror-thriller with a few minor comic elements. McDowell's story featured no Afterlife sequences, no other ghosts except for the Maitlands, and depicted Beetlejuice as a winged, reptilian demon who co-opted the position of an angel named Swallowtail, who helps ghosts lead peaceful existences while they await entry into their permanent resting places. Beetlejuice's goal is to kill the Deetzes rather than get them out of the house, and once he's dug up by the Maitlands, he cannot be controlled; the idea that he can be summoned and exiled by repeating his name three times was not added to the script until Burton became involved. This Beetlejuice wanders the "living world," assuming a variety of different forms to torment the Deetzes, and in the climax attempts to kill the Deetzes' nine-year-old daughter, Cathy, who was the only person able to see the Maitlands (as opposed to Lydia, who in McDowell's script was a disaffected, sixteen year old punk rocker whom Beetlejuice attempts to rape). The Maitlands then guide Cathy through an exorcism ritual that both allows them to be seen to the Deetzes and banishes Beetlejuice to another realm.