Saccharomyces cerevisiae
One of the main yeast species found in grapes and wines throughout the world. Most of the yeast strains used to ferment white wines are of this species.

Sauvignon Blanc
A popular white varietal in Europe, California and Australia. Sometimes called Fume Blanc in California, can be made into botrytised dessert wines.

Secondary fermentation
A fermentation that takes place after the primary fermentation. Both malolactic fermentation and the second alcoholic fermentation in sparkling wines are secondary fermentations.

Sediment
The residue of solids in a bottle of red wine that forms as the wine is matured.

Semillon
A lesser known white grape often blended with Sauvignon Blanc, especially in the production of the sweet wines of Sauternes, France.

Sensory evaluation
The assessment of wine based on sight, smell, taste and touch.

Serious
A description used for a wine that is of high quality.

Settling
The precipitation of the solid matter in wine.

Sherry
A fortified wine from Jerez de la Frontera, Spain, made by a controlled oxidation method, produced in many different styles, from sweet Cream sherry to very dry Fino sherry.

Shiraz
The Australian name for Syrah, a red grape variety.

Silky
Displaying a supple, smooth texture.

Single-vineyard wine
Wine made from grapes grown in one specific vineyard block, and bottled without being blended with wine from any other vineyard.

Skin contact
The time in the winemaking process when the juice of the grapes are in contact with the skins, extracting color, tannin and other substances.

Slightly sweet
Containing a barely perceptible amount of residual sugar.

Smoky
Displaying aromas that suggest smoke or smoked wood.

Smooth
A description for wine whose texture is not astringent.

Soft
Description for a wine whose alcohol and sugar dominate the tannin and acidity, resulting in a wine without roughness or hardness.

Solera System
A system used in the creation of Spanish sherry to carefully blend new and older vintages of wine to achieve a consistent style.

Sommelier
A wine steward.

Sour
The acid taste of wines that are made from unripe grapes.

Sparkling
Wine with an effervescence caused by a secondary alcoholic fermentation that leaves carbon dioxide trapped in the bottle.

Spicy
A term used to describe wine that displays aromas and flavors reminiscent of aromatic spices.

Spirits
In wine, the distilled alcohol used to make fortified wines.

Stabilization
The process of removing unwanted substances before bottling so they won't cause haziness or crystal formation in the finished wine.

Starter
A batch of active yeast that is used to begin fermentation.

Stemmer
A machine that separates the grapes from their stems, generally combined with a crusher and known as a "stemmer-crusher."

Stemmy
A term for wines that exhibit dry, woody tannins.

Stems
The woody part of a grape bunch that is high in tannin. Stems are removed before fermentation using a stemmer.

Still wines
Any wine without effervescence.

Stony
Displaying flavors or aromas that suggest stones or wet stones.

Structural components
A wine's alcohol, acid, tannin and sugar.

Structure
The impression conveyed by a wine's structural components.

Style
The characteristic combination of components - alcohol, acid, tannin and sugar - associated with the wines of a region, a winery or a particular winemaker.

Sulfer Dioxide
The compound used to inhibit the growth of unwanted microorganisms and to stop browning in wine.

Supple
A term meaning fluid in texture in the mouth, without any sharpness or roughness.

Sur lie
A French term meaning, literally, "on the lees." Generally refers to the aging of wines on the deposit of dead yeast that forms after primary fermentation. Sur lie aging imparts a toasty quality and enhances complexity.

Sweet
The taste of a wine with perceptible residual sugar, and the description of any dessert wine.

Sweetness
The impression of sugar in a wine, either from residual sugar or from alcoholic content.

Syrah
A distinguished red varietal made famous in the Rhone Valley, now grown in California and Australia, where is it known as Shiraz.

Table wine
Any still, dry wine less than 15% alcohol meant to accompany food.

Tannic
A term used to describe wines with a high tannin impression.

Tannin
A substance found in the skins, seeds and stems of grapes and a principal component of red wine's structure, extracted during fermentation while in contact with the skins and seeds. Oak barrels also impart some tannin to wine.

Tarry
Displaying aromas or flavors that suggest tar.

Tart
A term for the flavors and aromas associated with under-ripe fruit, or a term for wine with a high acid impression.

Tartaric acid
One of the essential organic acids found in wine.

Tartrates
Salts of tartaric acid that can form crystals when combined with potassium in unstabilized wine.

Taste
A general term for the total impression a wine gives in the mouth. Also refers to the primary tastes found in wine: sweetness, sourness and bitterness.

Tawny   
The brownish or amber color characteristic of wine such as port that has been aged in wood.

Terroir
A French word for the particular growing conditions of a vineyard, including soil, drainage, slope, climate, altitude, etc. that give the grapes grown there unique characteristics.

Tete de cuvee
The French term for a Champagne producer's best bottling.

Texture
A wine's feel or consistency in the mouth.

Thin
A term to describe wines that seem lacking in substance.

Tight   
A descriptor for wines whose aromas and/or flavors seem to be lacking in expression.

Toasted
An aroma found in Champagne reminiscent of toasted bread.

Toasting
The carmelization of barrel staves. The amount of "toast" can vary, imparting different characteristics to the wine.

Topping
A winemaking technique to control oxidation of wines aging in barrels where wine is added periodically to replace wine lost through evaporation.

Total acid
The measure of all a wine's acids taken together.

Troncais
A renowned forest near the French city of Moulins where oak is harvested to make wine barrels.

Underbrush
Aromas or flavors that suggest dampness, wet leaves or slight decay.

Unripe, under-ripe
Grapes that do not reach optimum ripeness; green.

Vanilla
Vanillin, imparted by aging in new oak barrels - particularly American oak - which has a vanilla-like odor.

Varietal
Describes the aromas and/or flavors characteristic of a particular grape variety.

Varietal character
The characteristics of a particular grape variety, or the characteristics of a wine that come from the grape variety from which it is made.

Variety
Sub-species of Vitis vinifera that are distinguished by yield, disease resistance or characteristic aromas or flavors of their grapes and the wine made from them.

Vegetal
A notable grassy or herbaceous "off" odor reminiscent of flavors such as bell pepper or asparagus; undesirable when excessive.

Vin
The French term for wine.

Vinegary
The "off" odor of ethyl acetate or acetic acid.

Vinification
The process of making grape juice into wine.

Vintage
The year in which a wine's grapes grew and were harvested. The term is often used as a synonym for the grape harvest.

Vintner
A person who makes or sells wine.

Viticulture
The science or activity of growing grapes.

Vitis vinifera
The species to which most of the world's wine grapes belong.

Weight
The impression of volume in the mouth that a wine imparts.

Well-balanced
Wines whose components - acid, alcohol, tannin and residual sugar - relate in a balanced way, so none overwhelm the others.

Wood tannin
Tannins that are attributable to the barrels in which the wine was aged, rather than from the grapes.

Woody
The "off" odor of wines stored too long in oak barrels.

Yeasts   
One-cell microorganisms that transform grape juice into wine.

Yeasty
The odor of the yeast used to ferment the wine.

Young
A fresh, fruity, un-oxidized and possibly slightly yeasty aroma.

Zinfandel
A distinguished and versatile red grape variety grown in California used to create red table wines, sparkling wines, blush wines and even port.