Wine Glossary of Terms
What is an appelation?
Often referred to as a geographic area where wine grapes are grown. If the appelation is named on the bottle label, it means that at least 85% of the wine is from that area. To label a wine with an appelation such as Sonoma Valley, Napa Valley, or Russian River Valley than with the more generic California, which means means the grapes could have come from anywhere in the state.
Appelation of Origion?
In the United States, appelations follow geopolitical lines and borders such as state and country lines rather than just geographical boundaries. Here is where we also define the natural features as soil types, climate and topography.
Source: Book - California Directory of Fine Wineries