Grain, usually barley, that has been allowed to sprout, used chiefly in brewing and distilling.

能够发芽生长的各类谷物，常指大麦，主要用于酿酒和蒸馏造酒。

youdao

Such was my introduction to aquavits (or aquavites or akvavits), high-proof liquors that have been made in Scandinavia since at least the 15th Century by distilling fermented potato or grain mash and flavoring it with savory, herbaceous ingredients.

WSJ: Sipping the Spirit of the North | Half Full