hell dust vs heroin

hell dust and heroin both are nouns.

Word	Noun	Adjective	Verb	Adverb
hell dust	Yes	No	No	No
heroin	Yes	No	No	No

As nouns, heroin is a hypernym of hell dust; that is, heroin is a word with a broader meaning than hell dust:

hell dust: street names for heroin
heroin: a narcotic that is considered a hard drug; a highly addictive morphine derivative; intravenous injection provides the fastest and most intense rush

Other hypernyms of hell dust include diacetylmorphine.

hell dust (noun)	heroin (noun)
street names for heroin	a narcotic that is considered a hard drug; a highly addictive morphine derivative; intravenous injection provides the fastest and most intense rush