Arcana

Arcana refers to secret knowledge or specialized information often associated with the mystical or esoteric. In various contexts, such as tarot cards or certain academic disciplines, "arcana" highlights subjects that require deeper understanding or insight, not readily accessible to the general public. For example, in tarot, the "Major Arcana" consists of 22 cards representing significant life lessons and spiritual themes. In broader terms, arcana can imply any complex or hidden aspect of a field that demands study and expertise, making it distinct from ordinary knowledge.