What does Formula-S stand for

I`ve heard the S stands for sport but I really think it`s just an abstract letter. It could`ve been Formula-Q , R, or whatever. Here`s some interesting advertising for the early S package and although it still doesn`t explain what "S" stands for, it`s interesting reading.http://www.earlyabodyforum.com/board/messages/394/19.html?1009435038