magnum opus

American  

noun

1. a great work, especially the chief work of a writer or artist.

   Proust's magnum opus is Remembrance of Things Past.

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magnum opus British  

noun

1. a great work of art or literature, esp the greatest single work of an artist

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magnum opus Cultural  

1. The most important work in a person's career, especially in literature, art, or scholarship: “Moby Dick was Melville's magnum opus.” From Latin, meaning “great work.”

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Etymology

Origin of magnum opus

Borrowed into English from Latin around 1785–95

Example Sentences

See Examples For:

magnum opus

He devoted nearly a fifth of his magnum opus to attacking the established quack system of mercantilism, which sought to maximize exports and minimize imports for the empty prize of a positive balance of trade.

From The Wall Street Journal ● Aug. 21, 2026

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

From BBC ● Oct. 31, 2025

Consumers’ Research, the Supreme Court reversed an opinion that Oldham presented as something of a magnum opus.

From Slate ● Jul. 10, 2025

It’s a magnum opus from the culinary icon behind Kogi, “L.A. Son,” and “The Chef Show” — a book built on balance and compassion.

From Salon ● May 23, 2025

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

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