stinkweed vs pennycress

stinkweed and pennycress both are nouns.

Word	Noun	Adjective	Verb	Adverb
stinkweed	Yes	No	No	No
pennycress	Yes	No	No	No

As nouns, pennycress is a hypernym of stinkweed; that is, pennycress is a word with a broader meaning than stinkweed:

stinkweed: foetid Eurasian weed having round flat pods; naturalized throughout North America
pennycress: any of several plants of the genus Thlaspi

stinkweed (noun)	pennycress (noun)
foetid Eurasian weed having round flat pods; naturalized throughout North America	any of several plants of the genus Thlaspi