pot marigold vs calendula

pot marigold and calendula both are nouns.

Word	Noun	Adjective	Verb	Adverb
pot marigold	Yes	No	No	No
calendula	Yes	No	No	No

As nouns, calendula is a hypernym of pot marigold; that is, calendula is a word with a broader meaning than pot marigold:

pot marigold: the common European annual marigold
calendula: any of numerous chiefly annual herbs of the genus Calendula widely cultivated for their yellow or orange flowers; often used for medicinal and culinary purposes

pot marigold (noun)	calendula (noun)
the common European annual marigold	any of numerous chiefly annual herbs of the genus Calendula widely cultivated for their yellow or orange flowers; often used for medicinal and culinary purposes