He paused and an impish smile crept across his face.
Globe and Mail
With his glasses and impish smile, he looks every inch the roguish professor you wish you’d had for history class.
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I miss his impish smile, always the portent of entertaining evenings.
Times, Sunday Times
I'm six feet tall; good hair; warm, impish smile; blue eyes, one on either side of my nose.
Times, Sunday Times
And there it was—that impish smile.
Smithsonian