peanut

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

• noun A prostrate southern Brazilian plant (Arachis hypogaea) widely cultivated in tropical and warm temperate regions, having yellow flowers on stalks that bend over so that the seed pods ripen underground.
• noun The edible, nutlike, oily seed of this plant, used for food and as a source of oil.
• noun A peanut-shaped piece of polystyrene, used in cushioning items during shipment.
• noun A small child. Often used as a term of affection.
• noun A person who is regarded as insignificant.
• noun Informal A very small amount of money; a trifling sum.

from The Century Dictionary.

• noun One of the edible fruits of Arachis hypogæn.
• noun The plant that bears these fruits, better known in England as groundnut. See Arachis. Also called ground-pea, earthnut, Manila nut, jur-nut, goober, and pindar.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) The fruit of a trailing leguminous plant (Arachis hypogæa); also, the plant itself, which is widely cultivated for its fruit.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A legume resembling a nut, the fruit of the plant Arachis hypogaea.
• verb transitive To pull on somebody's tie as a prank, causing the knot to tighten.

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

• noun pod of the peanut vine containing usually 2 nuts or seeds; `groundnut' and `monkey nut' are British terms
• noun 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
• noun a young child who is small for his age
• noun underground pod of the peanut vine
• adjective of little importance or influence or power; of minor status