arcane mystery 神秘的奥秘
hidden arcanum 隐藏的秘密
ancient arcanum 古老的奥秘
A: Do you think they will ever reveal the arcanum of the ritual?
A：你认为他们会揭示那个仪式的奥秘吗？
B: I doubt it; it is a sacred arcanum passed down through generations.
B：我不这么认为；那是代代相传的神圣奥秘。
1) 神秘的秘密
2) 深奥的知识
3) 炼金术中的奥秘
1. 神秘的奥秘
noun
1. A secret or mystery, especially one known only to a few.
Synonym: mystery, secret, enigma