Right Don. It depends on how you use the word.
As in the cite quoted by Kalosyni, the word used there is "sacred" and that too is ambiguous.
Epicurean philosophy is flatly natural and anti-supernatural.
But that does not at all mean that it isn't a highly focused system of thought that holds some things as "good" even to the point of "sacred" and other things "bad" to the point of evil. It's just that there's nothing supernatural at either end.