1. A dried plum. Prunes can be traced back to Roman times and have long been a popular northern European winter fruit because they could be stored without problem. Although any plum can be made into a prune, those with the greatest flavor, sweetness and firmness are best suited for that use. Commercial dehydration has replaced sun-drying as the primary method of producing prunes. Though the best prunes are found in the fall, they're available year-round. Prunes come in various sizes and are usually labeled small, medium, large, extra large and jumbo. When purchasing prunes look for those that are slightly soft and somewhat flexible. They should have a bluish-black skin and be blemish-free. Store them airtight in a cool, dry place (or refrigerate) for up to six months. Prunes can be eaten out of hand or used in a variety of sweet and savory dishes. Prune puree, which can be found in jars in most supermarkets, is broadly touted (primarily by the California Prune Board) as a fat substitute. In baked goods, substituting prune puree for butter or other fat can reduce cholesterol to zero and calories by up to 30 percent. The puree contributes moisture, a slightly chewy texture and a pruny flavor that can range from mild to moderately aggressive, depending on the other flavors in the food. 2. A variety of Italian plum. 3. In French, the word prune means "plum," while pruneau means "prune. "