definitely
Você sabe de certeza que aquele era Tom?
Are you sure that was Tom?
Quem sabe de certeza?
Who knows for sure?
De certeza que está bem?
Are you sure it's okay?
— O Leopardo (1963)
É de certeza que ele não saiu naquele dia.
It’s certain that he didn’t go out that day.
De certeza que já ouviu falar de mim.
You've definitely heard of me.
— Solaris (1972)