1. Someone who abuses or is addicted to an amphetamine, especially methamphetamine. This state is a thoroughfare for methamphetamine to the rest of the country, so it's little wonder that there are so many meth monsters here. I came out to see some devious little meth monster stripping parts from my car.

2. An epidemic of methamphetamine abuse or addiction. A number of states are pouring resources into law enforcement and prevention campaigns to slow the spread of the meth monster, which has been destroying communities around the nation.