Definition - What does Halbtrocken mean?
Halbtrocken is a German wine regulation term that means, "half dry," while this literal translation gives an indication of the how the wine will taste on the palate, wine labelled "halbtrocken," must meet specific criteria for acid and residual sugar level. Wine regulations regarding the characteristics of dry or sweet were regulated historically due to the tendency of winemakers in the colder growing regions of Germany, adding sugar to the winemaking process.
WineFrog explains Halbtrocken
In the lineup of dryness and sweetness in German wines, the half dry halbtrocken has more sweetness than trocken. Halbtrocken is a popular style of wine and accounts for nearly ¼ of all wines produced in Germany. The sweetness is measured by the levels of acidity and residual sugar in the wine. In order for a wine to be labelled as halbtrocken, the wine must have 18 grams of residual sugar per liter and can only exceed that amount if the acidity in the wine is within 10 grams of the residual sugar per liter.