In the United States, a "shot" typically refers to a standard serving of alcoholic beverages such as spirits (e.g., whiskey, vodka, rum). The standard size of a shot in the US is 1.5 fluid ounces (fl oz).
However, it's important to note that shot sizes can vary in different countries and contexts. In some places, a shot may be smaller or larger than 1.5 fl oz. Always check local regulations and customs regarding alcohol serving sizes.