cuckooflower vs bittercress

cuckooflower and bittercress both are nouns.

Word	Noun	Adjective	Verb	Adverb
cuckooflower	Yes	No	No	No
bittercress	Yes	No	No	No

As nouns, bittercress is a hypernym of cuckooflower; that is, bittercress is a word with a broader meaning than cuckooflower:

cuckooflower: a bitter cress of Europe and America
bittercress: any of various herbs of the genus Cardamine, having usually pinnate leaves and racemes of white, pink or purple flowers; cosmopolitan except Antarctic

Other hypernyms of cuckooflower include bitter cress.

cuckooflower (noun)	bittercress (noun)
a bitter cress of Europe and America	any of various herbs of the genus Cardamine, having usually pinnate leaves and racemes of white, pink or purple flowers; cosmopolitan except Antarctic