A is for Astringent: This is the term used to describe a wine that is high in tannin and has a mouth-puckering feel.

B is for Balance: Balance refers to the relationship between sweetness, acidity, tannin, and alcohol in a wine. In a well-balanced wine, one of the four won't overwhelm the rest.

B is also for Bordeaux: This term refers to both a region of France and the grape varieties grown thereCabernet Sauvignon, Merlot, Cabernet Franc, Sauvignon Blanc, Sémillon, and Muscadelle.

B is also for Burgundy: This term refers to both a region of France and the grape varieties grown therePinot Noir and Chardonnay.

B is also for Barrel-fermented: This means that the grape juice was fermented in wooden barrels, rather than stainless steel tanks. Typically, only white wines are barrel-fermented. Wines that are barrel-aged are placed in the barrels only after they have been fermented. Paradoxically, although the latter spend less time in the barrel, they have an oakier taste.

B is also for Biodynamic: This agricultural philosophy eliminates chemicals in favor of cover crops and companion plants to maintain a healthy growing environment. However, some question the rationale behind other tenets, like burying manure inside cow horns and pruning according to lunar cycles.

B is also for Brix: This is a measurement of the sugar content of grapes before they are harvested; the more sugar in the grapes, the more alcohol in the wine.

C is for Champagne: Only sparkling wine from the Champagne region of France can be labeled as such. The French would prefer that Americans only label their wine as méthode traditionnelle, but you'll also see méthode champenoise, both of which mean that the bubbles are produced by a secondary, in-bottle fermentation.

C is also for Clone: A clone is a cutting from a plant that has proven to grow good winemaking grapes. These days, all vineyards are propagated from clones.

C is also for Chardonnay: Chardonnay is a white wine from Burgundy known for its oaky, sometimes buttery, flavor and fruity aromas.

C is also for Cabernet Sauvignon: This is a Bordeaux variety that produces a tannic wine with the flavor of blackcurrants. Napa Cabs are (in)famously full-bodied.

C is also for Conaway, James: His books Napa and The Far Side of Eden tell the story of the county's struggle with land use, the dark underbelly of this appealing tourist destination.

E is for Estate-bottled: This indicates that the winery grew the grapes themselves, controlling the process from vineyard to bottle.

F is for Finish: This is the impression that you get in the back of your mouth and your throat after you swallow a wine.

L is for Legs: These are the rivulets you’ll see running down the sides of a wineglass after you swirl it. Though they used to be a sign of quality, they're now generally considered a result of surface tension and alcohol content.

M is for Malolactic fermentation: This is a secondary fermentation that makes a wine softer and less acidic. Red wine almost always undergo ML; whites may or may not.

M is also for Merlot: Though slandered in the film Sideways, Merlots can be wonderful high-alcohol, low-tannin wines with a jewel-like tone.

O is for Organic Wine: In order to be labeled organic, wine must be made from organically grown grapes, and produced without the addition of chemicals.

P is for Palate: You have a palate, but so does your wine.

P is also for Pinot Gris or Pinot Grigio: The French and Italian names of this variety both refer to a wine with medium to full body and low acidity.

P is also for Pinot Noir: This is a tough grape to grow, but produces a fruity, light-colored red wine.

R is for Rootstock: This is the stump, which has already established a root system, that grape growers will graft their desired clone onto. The section they attach is also called the scion, and will dictate what kind of grapes will grow.

R is also for Riesling: This oft-maligned variety is commonly considered to be overly sweet, but the best German Rieslings are dry.

R is also for Reserve: Historically, this term designates the best wine from a producer; however, it's not regulated in the U.S.

R is also for Racking: This term refers to siphoning the wine from one container to another after fermentation, leaving behind the sediment.

S is for Sulfites: Sulfur dioxide prevents wine from oxidizing or spoiling. Winemakers add it to wine, but it also occurs naturally during fermentation. If you think that red wine gives you a headache because of the sulfites, think again: White wines have more sulfites, since they're sweeter and thus more prone to spoiling.

S is also for Sauvignon Blanc: This white wine has a crisp taste, which comes from a higher acidity than you find in Chardonnay, for example.

S is also for Syrah: Known as Shiraz in Australia, this red wine has a deep color, a full body, and sometimes the aroma of tar or spice.

T is for Tannin: Tannin is a bitter substance that exists naturally in grape skins and seeds. It’s what makes your mouth feel dry when you taste some red wines.

T is also for Terroir: Terroir is roughly translated as the soil, climate, and other environmental factors that influence a growing grape.

T is also for Toast: The inside of an oak barrel is charred before wine is put in; a light or medium toast refers to how much it's been charred.