fanweed vs penny grass

fanweed and penny grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
fanweed	Yes	No	No	No
penny grass	Yes	No	No	No

As nouns, fanweed and penny grass are synonyms defined as:

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

Other synonyms of fanweed include field pennycress, French weed, mithridate mustard, stinkweed, Thlaspi arvense.

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