I'm not sure Buddhism would fall under the category of religion because, as I understand, Buddhism has no (diety) God, so,..
Structured observance of spirituality?
Philosophical Orientation?
The definition seems so subjective that it probably should be specified beforehand what exactly is being referred to. If it is a diety that is going to be worshipped, it would be a,...
System of piety?
"Pietism" was a movement in the 17th century in Germany similar to the goal of this forum, but the word "pious" is used in scripture referring to the Pharisees praying in public, so the referrence to piety is not exclusive to that movement.