arcanums

The archaeologist believed the symbol was an arcanum that could reveal the tomb's location.

考古学家认为，这个符号是一个可能揭示陵墓位置的秘密。

Few outsiders have ever learned the arcana of the island's boat-building tradition.

很少有外人曾学到这个小岛造船传统的奥秘。

The old cook guarded the arcanum of her family's noodle soup as if it were gold.

这位老厨娘像守护金子一样守护着她家汤面的秘密配方。