penny grass vs Thlaspi arvense

penny grass and Thlaspi arvense both are nouns.

Word	Noun	Adjective	Verb	Adverb
penny grass	Yes	No	No	No
Thlaspi arvense	Yes	No	No	No

As nouns, penny grass and Thlaspi arvense are synonyms defined as:

penny grass and Thlaspi arvense: foetid Eurasian weed having round flat pods; naturalized throughout North America

Other synonyms of penny grass include fanweed, field pennycress, French weed, mithridate mustard, stinkweed.

penny grass (noun)	Thlaspi arvense (noun)
foetid Eurasian weed having round flat pods; naturalized throughout North America	foetid Eurasian weed having round flat pods; naturalized throughout North America