"Allahu Akbar," the Muslim phrase allegedly uttered by Maj. Nidal Malik Hasan, the shooter who killed 13 and injured 30 at Fort Hood, Texas, yesterday, has become almost synonymous in Western brains with, "Die, infidel."

But the phrase, which means "God is great" or "God is greater," has a long history of versatility within both Muslim religion and Muslim culture -- it's uttered all the time and for a variety of reasons that have nothing to do with death.

It can be used as a form of praise, much like the word "bravo!" It can be used as an expression of surprise, like someone saying "Oh my God!" when they witness a car accident. Most commonly it's uttered in a religions context, included in the call to prayer, whispered into the ear of a newborn baby, and exclaimed at the slaughter of an animal. Of course suicide bombers who consider their actions to be righteous also use it so that they will die while praising Allah.

Perhaps the strangest incidence of "Allahu akbar" can be found in a pervasive folk legend involving none other than American astronaut Neil Armstrong. Supposedly, upon stepping on the surface of the moon, the famous "one step for mankind" astronaut heard the Muslim call to prayer in his headset (which includes the words "Allahu akbar"), but didn't know where they came from or what it meant. Upon returning to Earth and learning their meaning, he is said to have converted to Islam. Despite Armstrong denying the tale, it swept the Muslim world and continues to circulate. It became so all-pervasive that the U.S. State Department issued a blanket denial on his behalf in 1983.