What is Drug ?
Drug is (noun) 1. medicine They have found a new drug for people with arthritis. 2. a substance which affects the nerves, and which can be habit-forming The customs are looking for such things as drugs or alcohol. drug addict a person who takes drugs as a habit drug dealer a person who sells illegal drugs to other people (verb) to give someone a drug They drugged him and took him away in a car. (NOTE: drugging drugged)
source: Easier English, Student Dictionary Upper Intermediate Level