Wine Terminology

Oak Knoll District An AVA where wine is produced. (more info)
Oakville An AVA where wine is produced. (more info)
Obermosel One of the Mosel's Bereiche in western Deutschland where wine production takes place. (more info)
Oberösterreich A Bundesland of Österreich where little wine is produced. (more info)
Oenology The science of wine - fermeting, aging, and tasting. In American English one oft finds it written without the "O", but spelt that way I think obfuscates the Greek root.
Oeschle Scale A scale measuring the density of grape must to indicate grape ripeness and sugar content used in wine-making. It is named for Ferdinand Öchsle and widely used in the German-speaking parts of Europe. On the Öchsle scale, one degree Öchsle (°Oe) corresponds to one gram of the difference between the mass of one litre of must at STP and the mass of 1 litre of water (1kg). For example, must with a mass of 1100 grams per litre has 100 °Oe. This mass differential is mostly due to the dissolved sugar in the must, thus forcasting possible future alcohol content. It usually measured by using a refractometer to decide when to harvest grapes.
Offida A DOC wine produced in Italia. (more info)
Ogliastra (1) A province of Italia where wine is produced. (more info) (2) An IGT wine produced in Italia. (more info)
Ohio An American state where wine is produced. (more info)
Ohio River Valley An AVA where wine is produced. (more info)
Okanagan Valley A viticultural Region in British Columbia where wines are grown. (more info)
Oklahoma An American state where wine is produced. (more info)
Olbia-Tempio A province of Italia where wine is produced. (more info)
Old Mission Peninsula An AVA where wine is produced. (more info)
Olevano Romano A DOC wine produced in Italia. (more info)
Oltrepò Pavese A DOC wine produced in Italia. (more info)
Ontario A Canadian province where wines are grown. (more info)
Orange A GI wine produced in Australia. (more info)
Orange County A Virginia county where wine is produced in the United States. (more info)
Orcia An DOC wine produced in Italia. (more info)
Oregon An American state where wine is produced. (more info)
Oristano A province of Italia where wine is produced. (more info)
Ormeasco di Pornassio A DOC wine produced in Italia. (more info)
Orta Nova A DOC wine produced in Italia. (more info)
Ortenau A Bereich of Deutschland where wine production takes place. (more info)
Orvietano Rosso An DOC wine produced in Italia. (more info)
Orvieto A DOC wine produced in Italia. (more info)
Osco An IGT wine produced in Italia. (more info)
Österreich A country in Europe where wine is produced. (more info)
Ostuni A DOC wine produced in Italia. (more info)
Otago A Region of New Zealand. (more info)
Otoe County A county where wine is produced in the Nebraska. (more info)
Ottowa County An American county where wine is produced in Ohio. (more info)
Outer Coastal Plain An AVA where wine is produced. (more info)
Ozark Highlands An AVA where wine is produced. (more info)
Ozark Mountain An AVA where wine is produced. (more info)