I don't encounter words that I don't know at all very often, so I was pleased when I came across "adiaforical" in the Grantville Gazette in the story "The Rudolstadt Colloquy" by Virginia De Marce. According to the Philosophy Dictionary:
adiaforical is an adjective used by the classical Stoics to designate actions that are morally indifferent. On this view, we have no direct obligation either to perform or to avoid such actions, even when they might indirectly affect our general well-being. Thus, for example, although there is no duty to preserve one's own health, doing so is advisable, since it will probably feel good and improve one's capacity for doing what is right.I suspect that this will turn out to be a rather useful term although I suspect it describes a much larger memespace these days than it did back during the time of the Stoics.