Oh dear, look what's become of Jack's thread now!
I think "satan" is a Hebrew word, actually, meaning accuser. But don't take my word for it.
Judaism
Hebrew Bible
The original Hebrew term satan is a noun from a verb meaning primarily "to obstruct, oppose", as it is found in Numbers 22:22, 1 Samuel 29:4, Psalms 109:6.[6] Ha-Satan is traditionally translated as "the accuser" or "the adversary". The definite article ha- (English: "the") is used to show that this is a title bestowed on a being, versus the name of a being. Thus, this being would be referred to as "the satan".[7]
It seems to derive from Egyptian deity
Shaitan, and there's some compelling evidence by Ralph Elllis (I thought it was at the time I heard it anyway) that the Patriarchs of the Bible were those Egyptian Pharoahs who lost the civil war between North (Horus) and South (Set), hence "Set-inists." Fun times.
It's all about the Sun, innit.
I would also like to second tapitsbo's attempt to restore sanity: satanism like all the other ideologies is probably just a tool for groups and individuals to pursue their goals by donning whatever symbolic cloaks suit the occasion.
I'm not sure what the original point was, about Dworkin, whom I know nothing at all about.
It is a lot easier to fool people than show them how they have been fooled.