alfalfa vs lucerne

alfalfa and lucerne both are nouns.

Word	Noun	Adjective	Verb	Adverb
alfalfa	Yes	No	No	No
lucerne	Yes	No	No	No

As nouns, alfalfa and lucerne are synonyms defined as:

alfalfa and lucerne: important European leguminous forage plant with trifoliate leaves and blue-violet flowers grown widely as a pasture and hay crop

Other synonyms of alfalfa include Medicago sativa.

alfalfa (noun)	lucerne (noun)
leguminous plant grown for hay or forage	important European leguminous forage plant with trifoliate leaves and blue-violet flowers grown widely as a pasture and hay crop
important European leguminous forage plant with trifoliate leaves and blue-violet flowers grown widely as a pasture and hay crop