ˈfyüzəl- noun
Etymology: German fusel bad liquor
1. : an acrid oily liquid that has an unpleasant odor, that is obtained in small amounts as a by-product in alcoholic fermentation (as of potatoes, grain, or molasses), that consists of a mixture chiefly of alcohols (as isopentyl, active amyl, isobutyl, and normal propyl alcohols), and that is used especially as a source of alcohols and as a solvent
2. : amyl alcohol 2a