adv. In an impassible manner.
Usage examples of "impassibly".
She was drawn, overwhelmed, lost in the impassibly blue depths of his eyes, and felt the deep, pleasurable sensation again.
After locking up the bureau again, he walked to the window and gazed out as impassibly as he had done at the beginning of the interview, while Raffles took a small allowance from the flask, screwed it up, and deposited it in his side-pocket, with provoking slowness, making a grimace at his stepson's back.