impassible

I seemed already to be dead to the world, and a corpse with simply the impassible spirit outliving it.

Frederick changed colour and hung his head, but remained silent and impassible.

We expected to see him burst forth into a passion, but he remained impassible, he became pale.

Bertrand was silent, almost impassible in the midst of the seething effervescence of the people.

But he remained curiously impassible, looking at those present as if they were objects dimly seen afar off.