Mystery defined: something that is a secret, something where there is no clear explanation, something difficult to understand or explain or something unexplainable or unsolvable. NOUN
- An example of a mystery is the location of your Christmas presents.
- An example of a mystery is whether there is proof that God exists.
- An example of a mystery is how exactly people came to be.
- An example of a mystery is a situation where it is unclear who committed a crime. —Your Dictionary.com
Puzzle defined: a question or problem that requires thought, skill, or cleverness to be answered or solved: something or someone that is difficult to understand NOUN–Merriam-Webster.com
Quandary defined: a situation or circumstance that presents problems difficult to solve; predicament; dilemma NOUN–Collins English Dictionary – Complete and Unabridged © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003