ebonite vs caoutchouc

ebonite and caoutchouc both are nouns.

Word	Noun	Adjective	Verb	Adverb
ebonite	Yes	No	No	No
caoutchouc	Yes	No	No	No

As nouns, caoutchouc is a hypernym of ebonite; that is, caoutchouc is a word with a broader meaning than ebonite:

ebonite: a hard nonresilient rubber formed by vulcanizing natural rubber
caoutchouc: an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products

Other hypernyms of ebonite include gum elastic, India rubber, natural rubber, rubber.

ebonite (noun)	caoutchouc (noun)
a hard nonresilient rubber formed by vulcanizing natural rubber	an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products