peanut

or groundnut

Annual legume (Arachis hypogaea) and its edible seeds, which have the peculiar habit of ripening underground in pods. Native to tropical South America, peanuts were introduced early into the Old World tropics. Each pod contains one to three oblong seeds with whitish to dark-purple seed coats. Pound for pound, peanuts have more protein, minerals, and vitamins than beef liver, more fat than heavy cream, and more calories than sugar. They are pressed for edible oil, ground into peanut butter, eaten as snacks, and used in cooking. The plant is fed to livestock.

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