a large wine bottle for liquor or wine
"The sommelier uncorked the magnum of vintage champagne to celebrate the anniversary."
A bottle containing 1.5 liters of fluid, double the volume of a standard wine bottle.
"After the sound system started playing dancehall hits, everyone rushed to buy magnum bottles of tonic wine to celebrate at the street party."
A bottle of Magnum Tonic Wine, a fermented mead drink popular among Jamaicans and other Caribbean peoples for its intoxicating effects, vitamins and use as a purported sexual stimulant. The drink is highly associated with dancehall music and Jamaican pop culture.
"He decided to buy two bottles of magnums for the anniversary party."
Usage: While often used as a synonym for any large bottle of champagne or sparkling wine, "magnum" specifically denotes exactly twice the volume of a standard bottle; using it loosely to describe other oversized containers is technically incorrect. In casual conversation, speakers may apply it broadly to any large drink container, but precision requires adherence to its fixed 1.5-liter definition.
The word "magnum" comes from the Latin phrase magnum bonum, meaning "great good," which was shortened to label a large bottle size. The term was later adopted in 1935 as an official name for a specific type of handgun registered by Smith & Wesson Inc.