Peaceable Ambrose would have remonstrated, but Stephen was implacable.

Else, could I hear the perpetual revilings of her implacable family?

In a soliloquy he declares himself the implacable enemy of Cuzco and the Inca.

It was Karl Yundt who was heard, implacable to his last breath.

The sky was hard, implacable, without a star, but all the same translucid.

He constituted himself one of the most implacable enemies of Fantômas.

I have noticed an implacable thought in her eyes since the other evening.

There was no link wanting; the chain of heredity, logical and implacable, was unbroken.

All at once he could bear this implacable sphinx-gaze no longer.

Her eyes met his with a glance which had in it an implacable frankness.