Some people believe the “Rapture” and the “Apocalypse” will happen this weekend. What do these words mean exactly?

Who knows if REM had a specific date in mind when they sang their immortal chorus, “It’s the end of the world as we know it, and I feel fine.” But according to Harold Camping, a California-based Christian radio broadcaster, May 21, 2011 will bring about a rapture that will inevitably lead to the end of the world five months later. Before you throw away your “to do” list and cancel that hair appointment, let’s take a look at some useful cataclysmic terminology.

(Learn some additional words that describe when people interpret events as signs of the end of the world, here.)

Rapture is derived from the Latin raptus meaning “to seize, carry off.” Defined as “ecstatic joy or delight; joyful ecstasy” and “the carrying of a person to another place or sphere of existence;” the latter tends to coincide with what many believe is the origin of the modern meaning behind the phrase ‘The Rapture’ –  a Biblical reference from Thessalonians 4:15-17 and the following passage:  “… and the dead in Christ shall rise first. Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord.”

Armageddon is derived from the Hebrew Har Megiddon or Mount of Megiddo – a city located in central Palestine and, according to many Abrahamic religions, the site of the final battle during “end times.” The Greek translation is Harmagedōn and the Modern English variation we use today is a derivation of the Latin Armagedōn.

The doom in Doomsday is from the Old English dom meaning, “law, judgement, condemnation.” In medieval England many believed that the day of the last Christian judgment would occur once the earth reached 6,000 years old.

Originally, a series of “Doomsday books” signified the opposite of our apocalyptic sense of the term – a tome somewhere between a census and and a tax audit of England under William the Conqueror. The book is one of the best records of the day-to-day life in England at the time – more a celebration of mundane vitality than a chronicle of horrific ending. One of the more recent definitions of doomsday is a bit bleaker though – Doomsday is the name of an extraterrestrial monstrosity who notoriously took the life of Superman in a 1992 comic.

Many thousands of years later, some believe a biblical Doomsday is upon us once again. What do you think?