Definition - What does Buttery mean?
The term Buttery is a wine tasting descriptor that is usually used for a wine with a rich, creamy texture as well as aromas or flavors reminiscent of melted butter. This characteristic is often found in white wines that are aged or fermented in oak barrels. Prime examples of such wines include quite a few Chardonnays, Pinot Blancs and white Burgundies.
WineFrog explains Buttery
Wines with buttery characteristics are usually produced using malolactic fermentation, a process in which malic acid, the acid responsible for the tart taste in grapes, is converted into lactic acid to give the wine a softer "buttery" finish.
This Buttery characteristic develops in a wine due to the presence of lactic acid, a compound also found in fermented dairy products. The lactic acid created during the process of malolactic fermentation, ends up giving the wine a rich, creamy smoothness on the palate. Exactly like the reminiscent texture of butter, this trait is particularly popular among French and American Chardonnays.