What is the meaning of Mysterium?

Any of various unknown elements thought to make up existing forms of matter, or a substance seen as an elemental or pure form of something else.

The hypothetical source of a galactic radio emission at 1665 megahertz (later identified as due to hydroxyl radicals in interstellar space).

a mystery (something unexplainable)

a mystery (secret rite or worship)

mystery (secret rite or worship)

mystery (something unexplainable)

Source: wiktionary.org

See also