thumb|right|295px|Barrels waiting to be filled with grain whisky at the Whyte and MacKay Grain Distillery in Invergordon
Grain whisky normally refers to any whisky made, at least in part, from grains other than malted barley. Frequently used grains include maize, wheat, and rye. Grain whiskies usually contain some malted barley to provide enzymes needed for mashing and are required to include it if they are produced in Ireland or Scotland. Whisky made only from malted barley is generally called "malt whisky" rather than grain whisky. Most American and Canadian whiskies are grain whiskies.
Definition
Under the regulations governing the production of both Irish and Scotch whisky, malt whisky must be produced from a mash of 100% malted barley and must be distilled in a pot still. In the United States, whiskey produced at greater than 80% ABV is formally classified as "light whiskey" and cannot be labelled with the name of a grain or called malt, bourbon or straight.