cocktail

Early 17th century, from cock (“male bird”) + tail, in the sense “(a horse with its) tail standing up, like a cock’s”. The origin of the extension to “an alcoholic mixed drink” is unknown. One theory is that it refers to a stimulant (gingering), hence a stimulating drink; compare pick-me-up. Another attested use is for non-thoroughbred racehorses: these were considered "cock-tailed" due to their docked tails. This may have led to the term "cocktail" (sense 1) being used for an adulterated spirit.