carpenteria vs hydrangea

carpenteria and hydrangea both are nouns.

Word	Noun	Adjective	Verb	Adverb
carpenteria	Yes	No	No	No
hydrangea	Yes	No	No	No

As nouns, hydrangea is a hypernym of carpenteria; that is, hydrangea is a word with a broader meaning than carpenteria:

carpenteria: California evergreen shrub having glossy opposite leaves and terminal clusters of a few fragrant white flowers
hydrangea: any of various deciduous or evergreen shrubs of the genus Hydrangea

carpenteria (noun)	hydrangea (noun)
California evergreen shrub having glossy opposite leaves and terminal clusters of a few fragrant white flowers	any of various deciduous or evergreen shrubs of the genus Hydrangea