ar·​ca·​num är-ˈkā-nəm How to pronounce arcanum (audio)
plural arcana är-ˈkā-nə How to pronounce arcanum (audio)
: mysterious or specialized knowledge, language, or information accessible or possessed only by the initiate
usually used in plural

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The word arcanum (pluralized as "arcana") came from Latin arcanus, meaning "secret," and entered English as the Dark Ages gave way to the Renaissance. It was often used in reference to the mysteries of the physical and spiritual worlds, subjects of heavy scrutiny and rethinking at the time. Alchemists were commonly said to be pursuing the arcana of nature, and they sought elixirs for changing base metals into gold, prolonging life, and curing disease. The frequent association of the word with the alchemists' elixirs influenced the use of "arcanum" for "elixir."

Examples of arcanum in a Sentence

Recent Examples on the Web What became clear is that even publishers, agents, and retailers, who’ve rightly been focused on signing writers and selling books, didn’t appreciate how much the arcana of the business would matter in the move to digital platforms. Tim Carmody, WIRED, 3 Aug. 2010

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'arcanum.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


borrowed from Latin arcānum "secret, mystery, hidden place," noun derivative from neuter of arcānus "secret, private" — more at arcane

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of arcanum was in the 15th century


Dictionary Entries Near arcanum

Cite this Entry

“Arcanum.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2023.

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