indole vs heterocyclic compound

indole and heterocyclic compound both are nouns.

Word	Noun	Adjective	Verb	Adverb
indole	Yes	No	No	No
heterocyclic compound	Yes	No	No	No

As nouns, heterocyclic compound is a hypernym of indole; that is, heterocyclic compound is a word with a broader meaning than indole:

indole: a white or yellowish crystalline heterocyclic compound extracted from coal tar and used in perfumery, medicine, and as a flavouring agent.
heterocyclic compound: a compound containing a heterocyclic ring

Other hypernyms of indole include heterocycle, heterocyclic.

indole (noun)	heterocyclic compound (noun)
a white or yellowish crystalline heterocyclic compound extracted from coal tar and used in perfumery, medicine, and as a flavouring agent.	a compound containing a heterocyclic ring