A mystery or deep secret.
An elixir or secret remedy.
Something secret or unexplainable; an unknown.
Someone or something with an obscure or puzzling nature.
A religious truth not understandable by the application of human reason alone (without divine aid).
A particular event or series of events in the life of Christ.
A sacrament.
A secret religious celebration, admission to which was usually through initiation.
A craft, art or trade; specifically a guild of craftsmen.