hard drug vs cocain

hard drug and cocain both are nouns.

Word	Noun	Adjective	Verb	Adverb
hard drug	Yes	No	No	No
cocain	Yes	No	No	No

As nouns, cocain is a hyponym of hard drug; that is, cocain is a word with a more specific, narrower meaning than hard drug:

hard drug: a narcotic that is considered relatively strong and likely to cause addiction
cocain: a narcotic (alkaloid) extracted from coca leaves; used as a surface anesthetic or taken for pleasure; can become powerfully addictive

Other hyponyms of hard drug include cocaine, diacetylmorphine, heroin.

hard drug (noun)	cocain (noun)
a narcotic that is considered relatively strong and likely to cause addiction	a narcotic (alkaloid) extracted from coca leaves; used as a surface anesthetic or taken for pleasure; can become powerfully addictive