One of the levels of sweetness/dryness for champagne (or other sparkling wines). It can vary from quite dry to semi-dry (from a minimum of 12 to a maximum of 20 grams of sugar).
The subjective sweetness of a wine is determined by the interaction of several factors, including the amount of sugar in the wine, but also the relative levels of alcohol, acids, and tannins. Sugars and alcohol enhance a wine's sweetness, while acids cause sourness and bitter tannins cause bitterness. These principles are outlined in the 1987 work by Émile Peynaud, The Taste of Wine.