The definition of religion:
[Note: Geertz is one of the few scholars who admits that any definition in this area will be flawed. A good definition (one that is carefully made) will:]
…not establish anything by its self, provide a useful orientation of thought – a new way of looking at the topic and be an effective way of controlling and developing a new line of investigation.
[So, his definition of religion is:]
(1) A system of symbols which acts to (2) establish powerful, pervasive and long-lasting moods and motivation in men by (3) formulating conceptions of a general order of existence and (4) clothing these conceptions with such an aura of factuality that (5) the moods and motivations seem uniquely realistic. (pg. 90)
Geertz, Clifford. The Interpretation of Cultures, Basic Books 1973.