What do 'bling-bling' or , simply, to 'bling' mean? Where does the term come from ?

It means jewelry and comes from the sound it makes.

Hmmm... my jewelry doesn't go "bling bling." It doesn't really make any noise at all. I think it's in stealth mode. ...or maybe it's not big and clunky and gaudy enough.

Elexina, it's mostly referred to the bigger chains and jewelry that the musicians, such as rappers, gangsters, and thugs are wearing these days. But overall, like Jusork said, it's jewelry.