What is the difference between a mixed drink and a cocktail?

A cocktail is a kind of drink in which multiple ingredients are mixed, usually including at least one fruit juice and one hard liquor, although virgin (i.e. nonalocholic) cocktails also exist.
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A mixed drink is any drink that contains an alcoholic beverage as an ingredient. The definition of a cocktail is an iced drink made with wine or distilled spirits, and a variety of other flavoring ingredients. Some of the more well known cocktails are an Old Fashioned, a Cosmopolitan, a Martini, or Margarita. There are as many types of cocktails with many different names and new ones made up every day.
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