noun, plural ar·ca·na [ahr-key-nuh] /ɑrˈkeɪ nə/.
Origin of arcanum
Examples from the Web for arcana
Kornacki, on the other hand, appears to be far more comfortable with the kind of arcana found in The Almanac of American Politics.Steve Kornacki, MSNBC’s Brainy Replacement for Chris Hayes, Just Wants to Be Useful|David Freedlander|March 21, 2013|DAILY BEAST
This position is one of the arcana which were known to the ancients, and which are now lost.
He could have let you into the arcana rerum, which you have interests in knowing.
Ben-Ha-Zelah, re-kindled the fires of his furnaces and again applied himself to explore the arcana of alchemy.
He replied, "They are so; yet to us in our heaven they are not arcana, and consequently neither are they mystical."
Follow the noblest calling, the art of healing, and seek to penetrate the arcana of Nature.Mark Gildersleeve|John S. Sauzade