Dope
Dope is derived from the Dutch word for sauce (doop), and was first used in the early 1800's. In the late 1800's it started being used a drug term for smoking a saucelike version of opium. People who used drugs were dopes for acting silly or stupid. Starting around 1900 people began to refer to a drugged up horse as being doped. Dope also can mean an oil or lubricant, or a varnish that is painted on the fabric covering an aircraft. Dope was sometimes also was used to mean soda, possibly because Coca-Cola used to contain very small amounts of cocaine. (来源：EnglishCN英语问答中心[e问e答])