[ noun ] information known only to a special group <noun.communication> the secret of Cajun cooking
Arcanum \Ar*ca"num\, n.; pl. {Arcana}. [L., fr. arcanus closed, secret, fr. arca chest, box, fr. arcere to inclose. See {Ark}.] 1. A secret; a mystery; -- generally used in the plural.
Inquiries into the arcana of the Godhead. --Warburton.
2. (Med.) A secret remedy; an elixir. --Dunglison. ※ ||