I have long suspected that what we know today as a "cocktail" was invented to mask the taste of bad liquor. Indeed I've found several unsupported assertions to this effect online, generally pointing to an alleged Prohibition-era ruse (sweet ingredients, very cold temperature, fancy glass, adornments, etc.) to hide the awful taste of much bootleg gin. (At this point I feel compelled to point out that gin does not need to be bootleg to taste awful.)
I'm interested in locating some researched/documented support for all this.
EDIT: The use of the word "cocktail" to refer to an alcoholic drink is certainly older than the Prohibition. By "modern cocktail", I'm referring to 20-th century concoctions. My question is not about the origin of the word, but rather about the origin of using sweeteners, ice, and decorations to make unpalatable alcoholic drinks easier to swallow, and more precisely, I'm looking for researched/documented support (if such exists) for unsupported claims that during the Prohibition, cocktails became a popular solution to the problem of dealing with foul-tasting liquor. (The simplest support for this I can think of would be evidence of a sharp increase in the number of sweet cocktails whose invention can be dated to the Prohibition era, with all the usual controls for confounders, etc.)