A cocktail today usually contains one or more types of liquor and one or more mixers, such as bitters, fruit juice, fruit, soda, ice, sugar, honey, milk, cream, or herbs.
The earliest known printed use of the word cocktail was in The Farmer's Cabinet on April 28, 1803:
Drank a glass of cocktail—excellent for the head...Call'd at the Doct's. found Burnham—he looked very wise—drank another glass of cocktail.
The earliest definition of cocktail was in the May 13, 1806, edition of the Balance and Columbian Repository, a publication in Hudson, New York, in which an answer was provided to the question, "What is a cocktail?". It replied:
Cocktail is a stimulating liquor composed of spirits of any kind, sugar, water, and bitters—it is vulgarly called a bittered sling and is supposed to be an excellent electioneering potion, inasmuch as it renders the heart stout and bold, at the same time that it fuddles the head. It is said, also to be of great use to a Democratic candidate: because a person, having swallowed a glass of it, is ready to swallow anything else.
Compare the ingredients listed (spirits, sugar, water, and bitters) with the ingredients of an Old Fashioned.
The first publication of a bartenders' guide which included cocktail recipes was in 1862 — How to Mix Drinks; or, The Bon Vivant's Companion, by "Professor" Jerry Thomas. In addition to listings of recipes for Punches, Sours, Slings, Cobblers, Shrubs, Toddies, Flips, and a variety of other types of mixed drinks were 10 recipes for drinks referred to as "Cocktails". A key ingredient which differentiated "cocktails" from other drinks in this compendium was the use of bitters as an ingredient, although it is not used in many modern cocktail recipes.
The first "cocktail party" ever thrown was allegedly by Mrs. Julius S. Walsh Jr. of St. Louis, Missouri, in May 1917. Mrs. Walsh invited 50 guests to her home at noon on a Sunday. The party lasted an hour, until lunch was served at 1 pm. The site of this first cocktail party still stands. In 1924, the Roman Catholic Archdiocese of St. Louis bought the Walsh mansion at 4510 Lindell Boulevard, and it has served as the local archbishop's residence ever since.
During Prohibition in the United States (1920–1933), when the sale of alcoholic beverages was illegal, cocktails were still consumed illegally in establishments known as speakeasies. The quality of the alcohol available was far lower than was previously used, and bartenders generally put forth less effort in preparing the cocktails. There was a shift from whiskey to gin, which does not require aging and is thus easier to produce illicitly.
Cocktails became less popular in the late 1960s and 1970s, as other recreational drugs became common. In the 1980s cocktails again became popular, with vodka often substituted for gin in drinks such as the martini. Traditional cocktails and gin are starting to make a comeback in the 2000s.