Arachis is a genus of about 70 species of annual and perennial flowering plants in the family (Fabaceae), native to South America, and was recently assigned to the informal monophyletic Pterocarpus clade of the Dalbergieae. At least one species, the peanut, is a major food crop species of global importance; some of the other species are cultivated for food to a small extent in South America. Other species such as A. pintoi are cultivated worldwide as forage and soil conditioner plants, with the leaves providing high-protein feed for grazing livestock and a nitrogen source in agroforestry and permaculture systems.

The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, are a large and agriculturally important family of flowering plants. It includes trees, shrubs, and perennial or annual herbaceous plants, which are easily recognized by their fruit (legume) and their compound, stipulate leaves. The family is widely distributed, and is the third-largest land plant family in number of species, behind only the Orchidaceae and Asteraceae, with about 765 genera and nearly 20,000 known species.