Though no one in this wack ass world can really claim to be the definitive expert on slang, we got an email yesterday from someone whose credentials on this issue are as good as anyone's: Reginald C. Dennis, the former music editor of The Source magazine, back when it was The Bible of Hip Hop. Here is his explanation of The History of Wack:
Back in the 70s, in NYC, the term "wack" was used to describe the drug PCP or "Angel Dust." It was descriptive without being overly pejorative back then, but by the time "Rapper's Delight" dropped in ‘79, the word had taken on its current meaning, describing something as the opposite of "def" — which itself was derived from "the death"—meaning good.
We always assumed the word was spelled, w-a-c-k back then, but the rules of hip-hop style were still a few years from being invented. That [Keith Haring] mural probably went a long way to formalizing the word to outsiders, but as he clearly had his ear to the street, I am sure that he was merely following the spirit of the day.
When I was the music editor of The Source magazine (back when it was the magazine of record), we went to great lengths to create a hip-hop style guide for our editorial use. We were probably following what was already established in the likes of Word Up, SPIN and the Village Voice, but as far as we were concerned "hip-hop" would always be hyphenated and "wack" would never have an "h". For a time it seemed as if the community (both journalistic and hip-hop) moved in the same direction—even RollingStone and the NYT were following our various leads—but as more outlets joined the campfire we began to notice a decided erosion of discipline.
West Coast writers, for example, didn't say wack, they said "whacked," and their spelling reflected that subtle change. Soon you could see things spelled in The Source and Vibe one way and different ways in Rap Pages and The Bomb. The emerging freedoms that came along with the internet muddied the waters even further, and as hip-hop got bigger and bigger, that confusion seeped into the mainstream.
If TIME magazine, in an article about the rise of gangsta rap, could confuse the Dr. Dre of Death Row with MTV's Ed Lover, then how could they, in an attempt to beat the hip-hop mags to the punch, be expected to correctly spell the latest slang. Well, they couldn't, which is why they once, in a huge headline, spelled "jiggy" as "giggy."
By the time I founded XXL in ‘97, the barbarians had already begun massing in front of the gate and it would only be a matter of time before any attempt to maintain a consistent and unified notion of hip-hop style would end in frustration.
End of discussion.