Dictionary.com
definitions

magnum opus

See more synonyms for magnum opus on Thesaurus.com
noun
  1. a great work, especially the chief work of a writer or artist: Proust's magnum opus is Remembrance of Things Past.

Origin of magnum opus

Borrowed into English from Latin around 1785–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for magnum opus

jewel, masterpiece, masterstroke, masterwork, showpiece
British Dictionary definitions for magnum opus

magnum opus

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

Word Origin for magnum opus

Latin
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
Word Origin and History for magnum opus

"masterpiece, a person's greatest work," Latin, literally "great work" (see magnum + opus).

Online Etymology Dictionary, © 2010 Douglas Harper
magnum opus in Culture

magnum opus

[(mag-nuhm oh-puhs)]

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.”

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.