Definition - What does Oloroso mean?
Oloroso is a style of fortified wine made in southern of Spain in the region of Andalucia. Locally, it is called "Jerez" [Oloroso], though there are other styles. The Jerez style of Oloroso is a sherry with 17% alcohol content, and it is a dry style. It possesses nutty aromas and is of brown, nutty color.
WineFrog explains Oloroso
The local Jerez and special characteristics is made possible by a native yeast, flor. Barrels are filled 3/4 full and allowed to be naturally innoculated by the flor which float on the wine's surface. While other styles are permitted to be controlled with slow oxidation via the flor, Oloroso's oxidation is halted by earlier fortification, thus killing off the yeasts.
The result is a fortified, dry wine with full character and served as a digestif or meals of full character, such as game meats.