peanut vs Arachis

peanut and Arachis both are nouns.

Word	Noun	Adjective	Verb	Adverb
peanut	Yes	Yes	No	No
Arachis	Yes	No	No	No

peanut (noun)	Arachis (noun)
pod of the peanut vine containing usually 2 nuts or seeds; `groundnut' and `monkey nut' are British terms	a genus of plants with pods that ripen underground (see peanut)
a young child who is small for his age
widely cultivated American plant cultivated in tropical and warm regions; showy yellow flowers on stalks that bend over to the soil so that seed pods ripen underground
underground pod of the peanut vine

peanut (adjective)	Arachis (adjective)
of little importance or influence or power; of minor status