Happy dust is street jargon for cocaine, which is an addictive and highly dangerous drug. The term was coined in the 1900s and was frequently used by soldiers during the Vietnam War. The drug's euphoric effects can last anywhere from a few minutes to a few hours, depending on how much is taken. There are many synonyms for happy dust, including blow, coke, crack, nose candy, and snow. These slang terms are commonly used in the drug culture, and they're often used interchangeably. However, it's important to realize that using this kind of language normalizes and glamorizes drug use, which can lead to severe addiction and other dangerous consequences.