Agave sisalana vs century plant

Agave sisalana and century plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
Agave sisalana	Yes	No	No	No
century plant	Yes	No	No	No

As nouns, century plant is a hypernym of Agave sisalana; that is, century plant is a word with a broader meaning than Agave sisalana:

Agave sisalana: Mexican or West Indian plant with large fleshy leaves yielding a stiff fiber used in e.g. rope
century plant: tropical American plants with basal rosettes of fibrous sword-shaped leaves and flowers in tall spikes; some cultivated for ornament or for fiber

Other hypernyms of Agave sisalana include agave, American aloe.

Agave sisalana (noun)	century plant (noun)
Mexican or West Indian plant with large fleshy leaves yielding a stiff fiber used in e.g. rope	tropical American plants with basal rosettes of fibrous sword-shaped leaves and flowers in tall spikes; some cultivated for ornament or for fiber