Cannabis is a plant that
contains cannabinoids that are drugs. As a chemist, I typically don't refer to unrefined plant material as a drug. Because people don't typically consume caffeine raw, most people don't consider coffee consumption "doing drugs"; so, I believe cannabis deserves the same consideration.
Language matters, and I don't consider it to be pedantic to make this point (however subtle the distinction is).
Edit: And, for reference (since you missed the definition of cannabis):
Cannabis is a genus of flowering plants that includes three different species, Cannabis sativa, Cannabis indica and Cannabis ruderalis.