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

But for range and ambition, John Dos Passos’ three-volume magnum opus makes a claim to the accolade.

From The Wall Street Journal • Jun. 19, 2026

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

From BBC • Oct. 31, 2025

I sank into Randy Carter’s comfy couch, excited to see the Hollywood veteran’s magnum opus.

From Los Angeles Times • Aug. 14, 2025

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

From Slate • Jul. 10, 2025

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

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