hog peanut

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A twining North American vine (Amphicarpaea bracteata) in the pea family, having clusters of pinkish or white flowers and bearing three-seeded pods as well as basal or underground fleshy one-seeded pods.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun vine widely distributed in eastern North America producing racemes of purple to maroon flowers and abundant (usually subterranean) edible one-seeded pods resembling peanuts