What is mysterious mean?

1mysterious events or situations are difficult to explain or understand:
Eg:The police are investigating the mysterious deaths of children at the hospital.
2a mysterious person is someone who you know very little about and who seems strange or interesting [= enigmatic]:
Eg:I decided to find out more about my mysterious new neighbour.
3someone who behaves in a mysterious way says very little about what they are doing, in a way that makes you want to know more [= secretive]
Eg:She hid her thoughts behind a mysterious smile.

—mysteriously [adverb]:
Jackson had mysteriously disappeared.

adj.
1. 神祕的;不可思議的
the mysterious universe
奧祕的宇宙
A mysterious light came from the deserted house.
廢棄的房屋裡亮起了神祕的燈光。
2. 詭祕的
He is being very mysterious about his future plans.
對自己未來的打算,他顯得十分詭祕。