1.
Someone or something that is mysterious is strange and is not known about or understood.
He died in mysterious circumstances...
A mysterious illness confined him to bed for over a month...
The whole thing seems very mysterious...
ADJ
• mysteriously
A couple of messages had mysteriously disappeared.
ADV: usu ADV with v
2.
If someone is mysterious about something, they deliberately do not talk much about it, sometimes because they want to make people more interested in it.
As for his job-well, he was very mysterious about it.
ADJ: v-link ADJ, oft ADJ about n
• mysteriously
Asked what she meant, she said mysteriously: 'Work it out for yourself'.
ADV: ADV after v