Posted by Doug on October 08, 2003
Heavy metal --
Uranium, Plutonium, etc (even lead)
The connotation is that these metals are toxic or radioactive.
Heavy water is also toxic.
Intuitively, the term applies to music played on electronic instruments, modern instruments, ie "metal"
and not wood or gut. "Heavy" is the overpowering effect
on the nervous system - as if you were hit with several tons of active plutonium. "Heavy" is the depressing aspect of living in times where nuclear weapons exist.
That may not be the correct derivation of the term, but I think it fits.