common duckweed vs Lemna minor

common duckweed and Lemna minor both are nouns.

Word	Noun	Adjective	Verb	Adverb
common duckweed	Yes	No	No	No
Lemna minor	Yes	No	No	No

As nouns, common duckweed and Lemna minor are synonyms defined as:

common duckweed and Lemna minor: of temperate regions except eastern Asia and Australia

Other synonyms of common duckweed include lesser duckweed.

common duckweed (noun)	Lemna minor (noun)
of temperate regions except eastern Asia and Australia	of temperate regions except eastern Asia and Australia