truffle

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various fleshy, ascomycetous, edible fungi, chiefly of the genus Tuber, that grow underground on or near the roots of trees and are valued as a delicacy.
2. n. Any of various chocolate confections, especially one made of a mixture including chopped nuts, rolled into balls and covered with cocoa powder.

Century Dictionary and Cyclopedia

1. n. A subterranean edible fungus, especially of the ascomycetous genus Tuber. The common English truffle, T. æstivum, is roundish in shape, and is covered externally with polygonal warts. It is black outside, and brownish veined with white inside, and grows in calcareous soils, usually under birch- or oak-trees. Truffles are much esteemed as an ingredient in high-seasoned dishes. As there is no appearance above ground to indicate their presence, dogs and pigs are frequently trained to find them by the scent, and scratch or root them up. Many persons also become expert in selecting the places where they are likely to grow. The most famous field for the production of truffles is the old province of Périgord in France. The commonest species of the French markets is T. melanosporum. T. magnatum is the garlicscented truffle of Italy. Other edible species of Tuber are T. brumale, T. mesentericum, etc. The celebrated potato-like truffle of Italy, etc., is Terfezia leonis. The false truffle, which is frequently sold in the English and continental markets, is Scleroderma rulgare, allied, as is the so-called red truffle, Melanogaster variegatus, to the puffballs. See Tuber, 2, and compare tuckahoe.

Wiktionary

1. n. Any of various edible fungi, of the genus Tuber, that grow in the soil in southern Europe; the earthnut.
2. n. A creamy chocolate confection, in the form of ball, covered with cocoa powder.

GNU Webster's 1913

1. n. Any one of several kinds of roundish, subterranean fungi, usually of a blackish color. The French truffle (Tuber melanosporum) and the English truffle (Tuber æstivum) are much esteemed as articles of food.

WordNet 3.0

1. n. edible subterranean fungus of the genus Tuber
2. n. creamy chocolate candy
3. n. any of various highly prized edible subterranean fungi of the genus Tuber; grow naturally in southwestern Europe