How about we find out the origin of Slash's nickname from the artist formerly known as Saul Hudson himself?

"My best friend's dad is an actor named Seymour Cassel," explained Slash to Metal Hammer. "We used to ditch school and hang out at his house and he used to call me Slash and it was just habitual with him."

Slash continued, "I was on tour in Europe and I happened to run into him and we went to dinner. He told me that he called me Slash, cause I had to ask him, and he says it was always because I was in a hurry, hustling whatever it was I was hustling at the time and never had time to sit and chat. I was always sort of in passing and he just started calling me Slash."