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Synonyms

arcane

American  
[ahr-keyn] / ɑrˈkeɪn /

adjective

  1. known or understood by very few; mysterious; secret; obscure; esoteric.

    She knew a lot about Sanskrit grammar and other arcane matters.


arcane British  
/ ɑːˈkeɪn /

adjective

  1. requiring secret knowledge to be understood; mysterious; esoteric

"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

Other Word Forms

  • arcanely adverb
  • arcaneness noun

Etymology

Origin of arcane

First recorded in 1540–50; from Middle French, from Latin arcānus, from arc(ēre) “to enclose, restrain, ward off” (derivative of arca “box, chest, coffer”) + -ānus -an

Explanation

Something arcane is understood or known by only a few people. Almost everyone knows the basics of baseball, but only an elite few possess the arcane knowledge of its history that marks the true fan. A near synonym is esoteric, as in "relating to remote information or knowledge." Experts in academic fields often show off the depth of their knowledge by mentioning some arcane and esoteric fact as if it was common for everyone to know. The origin of arcane is Latin arcānus, "secret, closed," from arca, "a chest, box." Arcana (singular arcanum) are pieces of mysterious knowledge or information.

Keep Reading on Vocabulary.com

Vocabulary lists containing arcane

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.

Social media is awash in content about the arcane: how-tos for spellcasting, psychics claiming to foretell the future and endless posts about casting out demons.

From Salon • Apr. 1, 2026

Maybe that is true for the 500 biggest U.S. stocks but less so for a relatively arcane and less-researched sector such as BDCs.

From Barron's • Feb. 27, 2026

But that hasn’t stopped foreign academics, officials and business executives from trying to find out—and some are turning to arcane tea leaf-reading techniques dating back to the era of Mao Zedong.

From The Wall Street Journal • Feb. 15, 2026

Notable in an off-year special election about the arcane and complicated process of redistricting, 71% of likely voters said they had heard a significant amount of information about the ballot measure, according to the poll.

From Los Angeles Times • Oct. 30, 2025

By design they were arcane, opaque, illiquid, and thus conveniently difficult for anyone but Morgan Stanley to price.

From "The Big Short" by Michael Lewis