UC
Short for union coopérative.
Ullage
The gap between the top of the wine and the top of the bottle. It's not significant on most wines, but on a very old bottle it can be an indicator of how well the wine has been kept and how likely it is to be oxidised.
Unctuous
Unctuous wines feel rich and thick in the mouth.
Union Coopérative (UC)
A French winemaking cooperative.
Uva
Italian word for grape.
Uvaggio
Italian term for a wine made from several different grape varieties. Compare varietal.