What does fusel mean?
Fusel is a term used chiefly in brewing, distilling, and chemistry to describe the harsh, unpleasant elements found in crudely made spirits. Most often it appears in the phrase 'fusel oil', referring to a mixture of higher-boiling alcohols — such as isoamyl alcohol — that form alongside ethanol during fermentation. These compounds lend rough, solvent-like flavours to inadequately refined liquor and are blamed for much of the punishing aftereffect associated with cheap drink. By extension, 'fusel' itself can denote any inferior, harsh-tasting spirit. The word entered English from German, where 'Fusel' is colloquial for bad liquor, reflecting its origins in the vocabulary of Central European drinking culture. Today it survives almost entirely as a technical term: distillers speak of stripping out the fusel fraction to yield a smoother product, while connoisseurs may detect residual fusel notes in poorly distilled spirits. Its connotations are unfailingly negative — nobody praises a drink for its fusel.
nounFusel refers to inferior, harsh-tasting alcoholic liquor, especially as containing fusel oils — the higher-boiling alcohols produced during fermentation that give crude spirits an unpleasant, solvent-like flavour.
- Inferior or harsh-tasting distilled liquor, typically containing significant amounts of fusel oils.
- (Attributive) Relating to or denoting the higher (fusel) alcohols — such as isoamyl alcohol — formed during fermentation and concentrated in crude spirits.
"The cheap whisky had a distinct bite of fusel that betrayed its hasty distillation."
"Distillers carefully remove the fusel fraction during rectification to produce a clean, smooth spirit."
"He winced at the raw fusel character of the unaged spirit."
Rarely pluralised; when referring to individual fusel alcohols, chemists usually say 'fusel alcohols' rather than 'fusels'.
"The chromatograph separated the various fusels present in the sample."
That harsh, hangover-inducing edge in cheap booze has a name of its own — 'fusel', borrowed straight from the German word for bad liquor.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of fusel
The word comes from German 'Fusel', a colloquial term for inferior or harsh liquor, which was borrowed into English in the nineteenth century largely through the language of distilling and industrial chemistry. It is best known today through the compound 'fusel oil' (German 'Fuselöl'), coined to name the oily mixture of higher alcohols responsible for the rough taste of crude spirits.
How fusel is actually used
Almost always encountered in technical or trade contexts, most commonly in the fixed phrase 'fusel oil'. In everyday use it carries a strongly negative connotation, implying rough, poorly refined drink.
Easily confused with fusel
A fossil is the preserved remains of an ancient organism, whereas fusel denotes harsh, low-quality liquor or the oily alcohols found in it.