mysterious
- Difficult to explain or understand, often in a way that makes you curious or a little nervous.
- Keeping information secret in a way that makes others curious.
In a sentence
- A mysterious light appeared in the night sky and then vanished without a trace.
- The new student was mysterious about where she had lived before moving to town.
Usage note. Use 'mysterious' for things that genuinely puzzle or intrigue; 'secretive' is a better choice when emphasizing that a person is deliberately hiding information.
Where it comes from
English mysterious · entered English early 17th c.
Derived from Latin 'mysteriosus,' from 'mysterium' (mystery), which came from Greek 'mysterion,' meaning 'secret rite or doctrine,' related to 'mystes' (one who has been initiated) and 'myein' (to close the eyes or lips). It entered English in the early 17th century.