mystery
1. [ noun ] something that baffles understanding and cannot be explained
Synonyms: enigma closed_book secret
Examples:

"how it got out is a mystery" "it remains one of nature's secrets"

Related terms: perplexity perplex
2. [ noun ] (writing) a story about a crime (usually murder) presented as a novel or play or movie
Synonyms: mystery_story whodunit
Related terms: story detective_story murder_mystery
Similar spelling:   mastery
  mysterious
  masterly
  mycteria
  muster
  Mister
  Mester
  master