- mystery, enigma, secret, closed book - something that baffles understanding and cannot be explained; "how it got out is a mystery"; "it remains one of nature's secrets"
--1 is a kind of perplexity
Derived forms: verb mystify1, verb mystify2 - mystery, mystery story, whodunit - a story about a crime (usually murder) presented as a novel or play or movie
--2 is a kind of story
--2 has particulars: detective story; murder mystery