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Synonyms

magnum

American  
[mag-nuhm] / ˈmæg nəm /

noun

  1. a large wine bottle having a capacity of two ordinary bottles or 1.5 liters (1.6 quarts).

  2. a magnum cartridge or firearm.

adjective

  1. (of a cartridge) equipped with a larger charge than other cartridges of the same size.

  2. (of a firearm) using such a cartridge.

  3. Informal. unusually great in power or size.

    a magnum spotlight; a magnum dosage.
magnum British  
/ ˈmæɡnəm /

noun

  1. a wine bottle holding the equivalent of two normal bottles (approximately 52 fluid ounces)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of magnum

1780–90; < Latin, neuter of magnus large; in reference to firearms, originally used as a trademark by the Smith and Wesson Co.

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Yet long before earning all these accolades, Shakira was a teen girl in Baranquilla, Colombia, waiting in line at her local record store for a copy of Nirvana’s 1991 grunge magnum opus, “Nevermind.”

From Los Angeles Times • Mar. 18, 2026

After inspecting a gifted magnum of Chinese wine, he stressed that the country "knew how to produce" -- another worry for French producers.

From Barron's • Feb. 9, 2026

A magnum is not just twice the size of a regular bottle of wine: It is also, as a friend put it recently, “a supersized expression of joy.”

From The Wall Street Journal • Dec. 22, 2025

The following year Skepta released his own magnum opus, Konnichiwa.

From BBC • Oct. 31, 2025

“I don’t know what a magnum opus is,” said Wilbur.

From "Charlotte's Web" by E.B. White

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.