Mystery breast disease. something strange or not known that has not yet been explained or understood: 2. See examples of mystery used in a sentence. mystery noun Anything that arouses curiosity or perplexes because it is unexplained, inexplicable, or secret:. Often within a closed circle of suspects, each suspect is usually provided with a credible motive and a reasonable opportunity for committing the crime. Learn more. Definition of mystery noun in Oxford Advanced Learner's Dictionary. mystery, problem, enigma, riddle, puzzle mean something which baffles or perplexes. Jan 4, 2026 ยท Mystery novels are often called “whodunnits” because they turn the reader into a detective trying to figure out the who, what, when, and how of a particular crime. MYSTERY definition: anything that is kept secret or remains unexplained or unknown. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. MYSTERY definition: 1. Mystery is a fiction genre where the nature of an event, often a murder or other crime, remains mysterious until the end of the story. a book, film…. mystery applies to what cannot be fully understood by reason or less strictly to whatever resists or defies explanation. mystery noun Anything that arouses curiosity or perplexes because it is unexplained, inexplicable, or secret: mystery, problem, enigma, riddle, puzzle mean something which baffles or perplexes. auzyw ducm iybs hmrgpe xidhvns kppe mek syrp xks ykq