Fusel

Part of speech: adjective

Definitions

1. Containing or derived from fusel oil, a toxic mixture of higher alcohols produced during fermentation
2. Of or pertaining to fusel oil, the oily liquid byproduct formed when yeast ferments sugars
3. Involving fusel oil, the pungent alcoholic compound that accumulates as a secondary product in distilled spirits

Etymology: In German, "Fusel" was slang for cheap, harsh liquor, the kind that tasted bad and left a worse hangover. Its ultimate source is uncertain. Some scholars have linked it to older German words for something trivial or worthless, and others have suggested a Yiddish origin, but no explanation is firmly established. English borrowed the word for the oily by-products of fermentation that come over with distilled spirits. Chemists named these "fusel oil," a mixture dominated by amyl alcohols, after the rough, unpleasant spirits in which they were found. The name thus describes an unwanted fraction of the distillate rather than the drink itself.