dioon vs cycad

dioon and cycad both are nouns.

Word	Noun	Adjective	Verb	Adverb
dioon	Yes	No	No	No
cycad	Yes	No	No	No

As nouns, cycad is a hypernym of dioon; that is, cycad is a word with a broader meaning than dioon:

dioon: any cycad of the genus Dioon; handsome palmlike cycads with robust crowns of leaves and rugged trunks
cycad: any tropical gymnosperm of the order Cycadales; having unbranched stems with a crown of fernlike leaves

dioon (noun)	cycad (noun)
any cycad of the genus Dioon; handsome palmlike cycads with robust crowns of leaves and rugged trunks	any tropical gymnosperm of the order Cycadales; having unbranched stems with a crown of fernlike leaves