Botulism is the poisoning you get from toxins produced by naturally occurring Clostridium botulinum bacteria. It can be a food-bourne illness and it's the main reason you don't give babies honey or peanut butter.

Botox is a treatment made out of it because it's really good at blocking nerve signals so it "relaxes" involuntary muscles in the face that produce worry lines that make you look old. Derived from the name - BOtulinum TOXin. My dad has treatments to calm down involuntary twitches of his eye, and it works well for that.