certain
US /ˈsɝː.tən/
UK /ˈsɝː.tən/
1.
known for sure; established beyond doubt
:
•
It's certain that he will win the election.
•
Are you certain about your decision?
2.
specific but not explicitly named or stated
:
•
A certain person told me about it.
•
There's a certain charm about old houses.