alkene vs aliphatic compound

alkene and aliphatic compound both are nouns.

Word	Noun	Adjective	Verb	Adverb
alkene	Yes	No	No	No
aliphatic compound	Yes	No	No	No

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

alkene: any unsaturated aliphatic hydrocarbon
aliphatic compound: organic compound that is an alkane or alkene or alkyne or their derivative

alkene (noun)	aliphatic compound (noun)
any unsaturated aliphatic hydrocarbon	organic compound that is an alkane or alkene or alkyne or their derivative