The peanut, also known as the groundnut, goober (US), goober pea, pindar (US) or monkey nut (UK), is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics, important to both small and large commercial producers. It is classified as both a grain legume and, due to its high oil content, an oil crop. Atypically among legume crop plants, peanut pods develop underground (geocarpy) rather than above ground. With this characteristic in mind, the botanist Carl Linnaeus gave peanuts the specific epithet hypogaea, which means "under the earth".

Legumes are plants in the family Fabaceae, or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consumption; for livestock forage and silage; and as soil-enhancing green manure. Well-known legumes include beans, soybeans, chickpeas, peanuts, lentils, lupins, grass peas, mesquite, carob, tamarind, alfalfa, and clover. Legumes produce a botanically unique type of fruit – a simple dry fruit that develops from a simple carpel and usually dehisces on two sides.