mys·te·ri·ous 
/mɪˈstirijəs/ adjective
/mɪˈstirijəs/ adjective [more mysterious; most mysterious] : strange, unknown, or difficult to understand
▪ the mysterious ways of nature ▪ We heard a mysterious noise outside our tent. ▪ He died under mysterious circumstances. ▪ A mysterious illness has been spreading through the city. ▪ There's something mysterious about that old woman. ▪ Her behavior was very mysterious. ◊Mysterious people are often interesting because many things are not known about them.
▪ A mysterious stranger came to our door. ▪ the movie's handsome and mysterious main character
▪ the mysterious ways of nature ▪ We heard a mysterious noise outside our tent. ▪ He died under mysterious circumstances. ▪ A mysterious illness has been spreading through the city. ▪ There's something mysterious about that old woman. ▪ Her behavior was very mysterious. ◊Mysterious people are often interesting because many things are not known about them.
▪ A mysterious stranger came to our door. ▪ the movie's handsome and mysterious main character
be mysterious
: to talk or behave in a way that makes other people feel that you must have a secret
▪ What are you being so mysterious about?
▪ What are you being so mysterious about?
— mys·te·ri·ous·ly adverb
▪ He died mysteriously at the age of 32. ▪ She smiled mysteriously.
▪ He died mysteriously at the age of 32. ▪ She smiled mysteriously.
