Synonyms of mystery

Noun

1. mystery, enigma, secret, closed book, perplexity

usage: something that baffles understanding and cannot be explained; "how it got out is a mystery"; "it remains one of nature's secrets"

2. mystery, mystery story, whodunit, story

usage: a story about a crime (usually murder) presented as a novel or play or movie

Definition and meaning of mystery (Dictionary)