Oak chips
Small pieces of oak wood used in place of oak barrels in fermenting and/or ageing wine.

Oenology
The science of wine and winemaking.

Oenophile
A wine aficionado or connoisseur.

Off-dry
A wine that has the barest hint of sweetness; a slightly sweet wine in which the residual sugar is barely perceptible.

Old vine
Wine produced from vines that are notably old.

Old World wine
Wines produced inside of the traditional wine growing areas of Europe and North Africa.