penny grass vs mithridate mustard

penny grass and mithridate mustard both are nouns.

Word	Noun	Adjective	Verb	Adverb
penny grass	Yes	No	No	No
mithridate mustard	Yes	No	No	No

As nouns, penny grass and mithridate mustard are synonyms defined as:

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

Other synonyms of penny grass include fanweed, field pennycress, French weed, stinkweed, Thlaspi arvense.

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