Solvent: are aromas and flavors of higher alcohols (fusel alcohols). Similar to acetone, lacquer varnish and paint thinner aromas. It is an indication of stressed yeast and is undesirable. Cheap distilled liquor (where the last portion of the distillate is not discarded) often gives these notes. Reasons for the stress could be inadequate healthy yeast count, high gravity (too much sugar), high temperature accelerated fermentation, etc. In mead, the common reason is the use of inverted sugars or adulterated packaged honey.