American Viticultural Area | American term for delimited grape-growing areas distinguishable by geographic, climatic and historic features, and whose boundaries have been delineated in a petition filed and accepted by the federal government. In size, AVAs range from extremely small to extremely large. Unlike the European system of appellations, AVAs impose neither restrictions on grape or wine yields, nor guidelines as to which grape varieties may or may not be planted.
Dr Ian D’Agata, Native Wine Grapes of Italy (University of California Press, 2014), p567.
Oxford Companion to Wine 4th edition ed. Jancis Robinson MW and Julia Harding MW (Oxford University Press, 2015).