I long ago developed a very practical smile, which I call my "Noh smile" because it resembles a Noh mask whose features are frozen. Its advantage is that men can interpret it however they want; you ca

$And now here I was in McDonald's again for the first time since my earlier fracas. I vowed to behave myself, but McDonal — Bill Bryson, The Road to Little Dribbling: Adventures of an American in Britain$

I long ago developed a very practical smile, which I call my "Noh smile" because it resembles a Noh mask whose features are frozen. Its advantage is that men can interpret it however they want; you can imagine how often I've relied on it.