The reason their are slang terms for drugs is so that police and other unwanted listeners are able to understand that drugs are being talked about
Do a Google search for "slang terminology for illegal drugs". It will give you several websites.
No it's not
Some slang terms for amphetamines are bennies, uppers, whiz, lid proppers, rippers, and speed. Amphetamines are drugs that are stimulants.
Drugs are usually symbolized using images or icons that are commonly associated with drug use, such as pills, syringes, or leaves. They can also be symbolized using slang terms or codes that refer to specific drugs, such as "420" for marijuana or "E" for ecstasy.
Some slang terms for arsonist are firebug, torch, and pyro.
The slang terms I'm familiar with are: P.I. Private Eye, Peeper and Dick
Slang. One that takes or is addicted to drugs
Slang for a joint. It's "doobie".
Restroom IS a slang term. Click on the related question
There aren't slang terms for people's names.
Doop is slang for dope which can be used to describe something as cool, or it can be slang for a number of drugs.
One will find that there is no slang term for brake lines, as they are not referred to in another way. There are many other slang terms for street etiquette, but there is not a slang therm for 'brake line' currently.