A “fifth” refers to a traditional bottle size for spirits, once equal to one-fifth of a US gallon. While this volume (757ml) is less common now, many bottles of distilled spirits, including vodka, are still sold in a size close to this traditional measurement, typically 750ml. This standard capacity allows for consistent pricing and serving measurements across different brands and regions.
The standardization of spirit bottle sizes simplifies trade and consumer understanding. The near-universal adoption of the 750ml bottle, a volume roughly equivalent to the old fifth, provides a familiar benchmark. This facilitates comparisons between brands, allows for easier calculation of drink recipes, and aids in inventory management for bars and retailers. The historical usage of “fifth” persists in informal conversations, highlighting the enduring legacy of this traditional measurement.