The original Japanese for "Saiyan" was "Saiyajin".
The jin, is a notifier of a person; thus, he is one of "Saiya" or of the "Saiya" race. Because this was translated to Saiyan (ex. Romujin -> Roman), the J is absolutely unnecessary, however. Then again, it was never necessary in the first place.
The majority of people who put SSJ are people who grew up influenced by earlier boards and fans who were...more deeply invested in the series..
Saiya-jin is the Japanese version. Saiya came from the word, "Yasai" which means vegetable. Jin at the end signifies person/people. So the name fully means, vegetable people hence why the names of Saiya-jin are vegetables. I still say saiya-jin when actually talking about it but for the sake of this board, I stick with Saiyan.
"why is this a topic?... -1 for humanity" - Ninja_Toast PSN: Soukyuu-kun Jap PSN: DarkYakumo
Because DBZ (and anime in general) was... I don't know, "underground," in those dark days of the early and pre-Internet, the only way to see DB was poor-quality (often VHS) fansubs, or some other language (original Japanese, Chinese, Korean, etc.). Because of that, the fans (and the people making the fansites) didn't have the "official" romanization of "Saiyan" to go by, so they/we settled on a simple, direct transliteration of the Japanese--Saiyajin, which, IIRC, was written with a reversed "vegetable" character and the normal "person" character at the end.
So, basically, you can tell the age of a DBZ fan by how they write the word "saiyajin".
Also: you abbreviate "Japan" to "JPN." That ~other~ term is a racial slur.
"...Blame this on the misfortune of your birth." -Char Aznable