Definition - What does Dry Extract mean?
"Dry Extract" is a term based on the theoretical value of a wine if it were to be put through a centrifuge to remove all the water. The powder which would remain is the dry extract. This is the physical aspect of wine that is directly attributed to its body and flavors.
WineFrog explains Dry Extract
The amount of dry extract a wine contains will determine the fullness of its body. The higher the volume, the fuller-bodied the wine will be. The lower the volume, then the wine will have a lighter body.
It is not a term used often, however in some countries it has become a required analysis. It is measured in grams and the average dry extract for white wines is between 15-20 grams/Liter. For red wines, the average is around 20-30 grams/Liter.