Which characteristic defines a 'dry' wine in the context of a French wine label?

A 'dry' wine is defined by having little to no residual sugar. In wine production, residual sugar refers to the natural grape sugars that remain in the wine after fermentation. When fermentation is complete, if most of the sugars have been converted to alcohol, the wine is considered dry. This characteristic is important in distinguishing dry wines from sweet wines, which contain higher levels of residual sugar.

In the context of a French wine label, this definition is particularly relevant as it is a common tasting note and descriptor for many wine classifications. Dry wines tend to be favored for their crisp texture and ability to pair well with a variety of foods, making them particularly popular among wine drinkers who appreciate less sweetness in their beverages.

High acidity does contribute to the perception of dryness but is not a defining characteristic of dry wines. Similarly, high tannin levels can be found in various styles of wine, both dry and sweet, but they do not specifically indicate dryness. Significant residual sugar, on the other hand, clearly defines wines that are not dry and instead indicate a sweet profile. Therefore, the defining characteristic of dry wine in French wine labeling is having little to no residual sugar.