Origin of an idiom: “My foot!”

From Saul Maydup, Idioms and How They Got That Way (2019): We know the expression “My foot!” as a way to signify indignant disbelief or shock: “Safe? My foot! He was out by a mile!” But it may surprise you to learn that the expression has its origin in the world of feet — in the world, that is, of poetry. The expression was born in 1727, during one of Jonathan Swift's many visits to the Twickenham…