Definition - What does Magnum mean?
Magnum is the name for a 1.5L bottle of wine. Magnum bottles are the equivalent of two regular bottles of wine. This 1.5L bottle size is the next largest common bottle size after the standard 750ml bottle, however, two uncommon bottle sizes (Fifth and Liter) sit between the Standard and the Magnum. The bottle name is in reference to the Latin word “Magnum”, which means “large”.
WineFrog explains Magnum
The use of varying bottle sizes in wine storage and sales started in the early to mid 1700s, after cork was discovered, and Magnum was one of the original sizes developed when the larger bottles were conceived. Magnums were rare, so winemakers and estates had to request special Magnum bottles and usually only did so for special occasions or wines.
Magnums are used for special wines, especially in Bordeaux, Champagne and Burgundy, because the lower ratio of wine to air trapped in the bottle allows wine to age at a slower rate. Slower aging speed creates unique characteristics, aromas and flavors that wouldn’t appear in the wine from smaller bottles. Wine can also be left to age for a longer period of time.
While Magnums are the perfect bottle for parties, they aren’t easily available. Producers and wine sellers don’t advertise magnum sizes for their regular wines because the cost of creating them isn’t met by an equal demand. Wine agents or stores have to specifically request the Magnum (or larger) bottle size of a specific wine, so, many stores don’t stock them because they are difficult to store and display (magnums are often displayed at the back of the store).