abboccato - Italian - Medium sweet.

abocado - Spanish - Medium sweet.

abv (alcohol by volume) - the measure of alcohol content shown on wine labels.

AC - Used in France as an abbreviation of Appellation Contrôllée and in Portugal for Adega Cooperative, a type of regional wine cooperative.

acetaldehyde - One of a number of chemical compounds called aldehydes produced by the oxidation of alcohol. In some wines it can add to the complexity of the wine and heighten its bouquet, though the presence of too much is a sign of spoilage.

acetic acid - The acid which gives vinegar its distinctive sour taste, it is produced by the oxidation of alcohol. In small amounts it may enhance the flavor of a wine.

acid - A class of chemical compounds, typically corrosive and sour-tasting, some of which appear naturally in wine. A certain amount of acid is vital to the preservation of wine. See also acetic acid, acidification, acidity, ascorbic acid, carbonic acid, citric acid, lactic acid, malic acid and tartaric acid.

acidification - The process of adding natural fruit acids to wine to increase its overall acidity. This practice is allowed in some regions and not in others.

acidity - A necessary flavor component of wine caused by the presence of acid. Acidity is needed to balance the other flavors of fruit and sweetness. A wine with too little acidity will taste flat, with too much it will taste sharp. See also soil acidity and volatile acidity.

acidulation - Acidification.

adamado - Portuguese - Sweet.

adega - Portuguese - A wine estate or wine cellar.

aeration - The deliberate exposure of wine to air. During fermentation a certain amount of oxygen is required to activate the yeast, but too much could result in oxidation. Aeration prior to serving can sometimes bring out qualities in a wine that otherwise would be hidden.

aftertaste - The flavor that lingers in your mouth after tasting or swallowing. It can be either pleasant or unpleasant- or non-existent, which would indicate a neutral-flavored wine. Harsh or unpleasant aftertaste might indicate the presence of excessive acidity or tannin in the wine. A synonym for finish.

age, aged and ageing - Refer to the maturation process of wine in general, but allude to that property of fine wine that allows it to undergo almost magical transformations over time. It is important to note that not all wine will improve with age -- generally only finer wines will, and even those only when carefully stored. Many good wines are made with the intention that they be drunk young. Among the signs of ageing in wine are a mellowing of harsh flavors, the appearance of sediment and a change in co lor -- in reds to a pale brick color and in whites to a honey-like yellow and eventually to tawny brown. Wine that has aged less gracefully may suffer from oxidation or maderization. In general, the tannin in red wine allows it to continue to improve for longer periods than white. Some great wines -- botrytized wines, some fortified wines and fine wines made from Cabernet sauvignon, Nebbiolo and certain other grapes to name a few -- can improve for many decades. See barrel ageing and bottle ageing.

alcohol - One of the basic constituents of wine, alcohol is a tasteless and colorless chemical that occurs naturally during fermentation when sugars from grape juice are processed by yeast. The alcohol that is found in wine is primarily ethyl alcohol though other alcohols can be found in smaller amounts. See iso amyl alcohol. The alcohol content of wine ranges from about 8% to 14% by volume, and the correct amount of alcohol is essential to a wine's body and balance. Alcohol is the intoxicating component of wine, and most countries require the alcohol content of a wine to be shown on its label.

alcoholic - Term used to describe a wine out of balance due to an overabundance of alcohol.

amabile - Italian - Medium sweet.

American Viticultural Area - Abbreviated to AVA - a system for controlling geographical designations for wine-producing regions, developed by the U.S. government along the lines of the French Appellation d'Origine Côntrollée. Criticized by some for being too lenient compared to its European counterparts, the system is designed to allow for the development of the country's still nascent wine industry.

Amontillado - A style of Spanish sherry, darker than fino with a slightly nutty flavor.

ampelography - The branch of botany concerned with the classification of the vine species Vitis and its cultivars.

Anbaugebiet - German - Any of the thirteen specific wine producing regions recognized under German wine law. See Qualitätswein bestimmter Anbaugebiete.

antioxidant - As it relates to wine, any chemical that impedes oxidation. See ascorbic acid.

AOC - Short for Appellation d'Origine Contrôlée.

apéritif - French - A beverage served before a meal intended to stimulate the appetite. Traditional apéritifs include many fortified wines, such as sweet and dry vermouth, Lillet and Dubonnet, as well as champagne and other sparkling wines and Sauternes.

appellation - French - The name of a wine, particularly regarding its geographic origin.

Appellation Contrôlée - Short for Appellation d'Origine Contrôlée.

Appellation d'Origine Contrôlée French Abbreviating to AOC - this is the highest level of the French system of geographic naming control. It was developed in the 1930s to regulate French wine production, purity and geographic origin, and is administered by the Institut National des Appellations d'Origine, or INAO. Rules for AOC qualification are stringent and far-reaching, covering everything from grape varieties and winemaking methods to yields and vine density. Wines from regions that have not earned AOC status may fall into the VDQS category or vin de pays, or they may simply be vin de table. The very successful AOC system has been emulated -- with mixed results -- by most wine-producing countries as well as the European Union, whose quality wine designation is its parallel.

ascorbic acid (Vitamin C) - Can be found in greater concentration in unripe grapes than in ripe ones, but often is added to wine as an antioxidant.

assemblage - French - The blending of wines, particularly finer wines. See also, coupage.

astringent - Causing a puckering, or drying feeling, in the mouth. In wine it is due to an abundance of tannins. The sensation is similar to that caused by drinking over steeped tea. A small amount of astringency is expected in some wines, especially young red wines made from powerful varieties such as cabernet sauvignon.

asztali bor - Hungarian Table wine.

aszú - Hungarian - Botrytis-affected grapes. See Tokay Aszú.

Ausbruch - Sweet wine made from naturally dried grapes, sometimes called "burst" wine

Auslese - German - The third highest category of the Qualitätswein mit Prädikat category of German white wines, as described by German wine law. Its name means "selected harvest", and the grape bunches are harvested at a later stage of ripeness than those for the less ripe Spätlese wines. See also Beerenauslese and Trockenbeerenauslese.

austere - Descriptive term for a wine that is out of balance with too little fruit to compensate for an abundance of tannin and/or acidity.

autolysis - As it relates to wine, this is the decomposition of dead yeast cells after fermentation. Through lees contact, (see sur lie), this process can impart complex flavors to wine. There is some debate as to the optimal amount of time before autolysis produces the most profound effects, so the duration of lees contact ranges from some months to many years.

AVA - Abbreviation of American Viticultural Area.