Actually, the word religion is of latin roots. Ligo means to bind together or to tie. Religo means to bind together over again. If someone does something "religiously" they have bound themselves to that task. It does not imply a higher power. However, there are many iterations of the word. Thomas Paine even wrote a treatise on the meaninglessness of the word religion. He claimed it was "vague and unexact" for the very reasons we are talking about it here; it has a different meaning for everyone. Paine went on to say, in fact, that religion has a different meaning to the Chinese (I believe he was referring to Buddhists), the Brahmans (India, Japan, and parts of China), Christians, Jews, Muslemen (Muslims), etc. The only reason I posted my reply yesterday was because there is a tendency among some to dismiss and belittle anyone who does not follow the same belief system (or those who don't have one) as the Christian majority. They will often use language to accomplish that goal. "Atheism" used to be aquainted with immorality. Some dictionaries actually had that as one of the definitions. So despite the roots, common use today allows for many different interpretations of the word religion. Many other words have likewise changed definitions through popular use. The word gay used to mean happy almost exclusively. Now it is far more common to hear it refer to homosexuality. So religion is not the exclusive domain of the theists. It all depends on who you hang out with.