O
- Oak
- Tree from the genus Quercus (synonyms Lepidobalanus and Leucobalanus). It is widely used to produce barrels. The tastes yielded by French and American species of oak are slightly different, with French oak being subtler, while American oak gives stronger aromas.
- Oak chips
- Small pieces of oak that are used during the aging process of a wine to give the impression that it has been aged in new oak barrels. It is used mostly in the production of inexpensive wines and their use may even be illegal in some regions.
- Oaky
- A tasting term for wines. Oaky wines are said to have mainly aromas and/or flavors of butter and toast.
- Odor
- The olfactory perception of the volatilized chemical compounds found in wine. It may be sensed by the nose when it sniffs the wine or by the vapors that reach the nose through the nasal passages. More appropriate words to describe the odors found in wine are “aroma” and “bouquet” (unless you want to give a negative connotation to what you smell in the wine).
- Oechsle
- The German ripeness scale (same as the Brix scale).
- Oenology
- British spelling of enology, the science of wine production.
- Off
- A term meaning that there is something wrong with the aromas and/or flavors of a wine.
- Off dry
- A description for a wine that gives you a minor impression of being sweet.
- Oidium
- Powdery mildew. It is a fungal disease that affects the vine and is one of the easier diseases to spot, as its symptoms are quite distinctive. Infected plants will display white powder-like spots on the leaves and stems.
- Old World
- Wines produced in the traditional wine growing areas of Europe; however, it can also represent a style (meaning that a wine produced outside of Europe can be “Old World” as well) in which the wines are less fruity and more subtle than “New World” wines.
- Old World wine
- Wines that come from the traditional regions in Europe are branded as such. As a general rule (but with plenty of exceptions), these wines would display the terroir of where the grapes are grown, while their “New World” counterparts would have a more fruity flavor profile.
- Open
- After a wine has been exposed to air (“aerating” or “breathing”), it shows its full potential and inherent qualities.
- Organic viticulture
- Grapes grown in a way that avoids or largely excludes the use of synthetic fertilizers, herbicides and pesticides. Inputs of organic materials and lack of chemical sprays encourage a healthy soil biota, which in turn should enhance the growth of the vines and improve the quality of the grapes.
- Overripe
- A tasting descriptor for wines made from grapes that were harvested late. The acidity consequently is lower, the alcohol higher and the aromas and flavors of very ripe fruit become dominant (ripe prune and raisins are classical examples).
- Oxidized
- A wine that has been exposed to air and that has lost (partially or totally) its original qualities.
