Saying something is cool. Most heard in big cities. Or, a drug. (Ex. Cocane/Mary J/ Dope)

Music so good it could elicit sexual arousal.

Old people definition: Marijuana
Southern definition: Meth
Northern definition Heroin
Also dope can mean awesome.

A word used to describe just about anything good in life, good news, a sick skateboard trick, a nice sports car, etc. Also one of the most casual yet satisfying words in modern slang. It can be used to varying levels of intensity anywhere from a casual "dope" to a mega hype "that's freaking dope man!".

Some belittle this word's meaning to purely a reference to drugs, but I'd argue that's like one of those #3 definitions on dictionary.com, like who cares, only the #1 definition matters.

People who do not do drugs call Marajuanna Dope.
People who do Marajuanna call Heroin Dope.
Word has also been used to describe how good somthing is.

In the 60's thru 80's "dope" usually meant marijuana. See the famous quote from the Fabulous Furry Freak Brothers ("Dope will get you through times of no money better than money will get you through times of no dope!"). For a time, "dope" became a more generic term, often used for heroin (which used to be called "smack" or "junk"). "Weed" is now usually preferred for marijuana.

These days, dope is most often used to refer to heroin, though it can refer to any drug that's common in a community.

A stupid person. Noun
A buffoon, simpleton, dolt or idiot.
Charlie Brown may say block-head.