sacré bleu
The termsacré bleuis a dated, stereotypical French expression meant to express astonishment, shock, or amazement. In historical France, Christians were worried about people taking their lord’s name in vain. So, they proposed all kinds of alternatives to saying such expressions as Mon Dieu!(“My God!”) likemorbleuandparbleu,akin to English euphemisms likegollyorgoshforGod.Bleu, meaning “blue” in French, rhymes withDieu, making it a handy way to avoidblasphemy. One of these ways to avoid explicitly swearing wassacrebleu.Typically written in French as one word and without an accent,sacrebleuis attested to as early as 1552, although it didn’t really catch on until the early 19thcentury.Sacréin French means “sacred,” so taken together,sacrebleu,literally means “Holy blue!” instead ofsacré Dieu(“Holy God!”)
By 1805,sacrebleu, written variously assacré bleuorsacre bleuin English, was used in writings by the British about French people. In order to show how French a person or character was, they might sprinkle in asacré bleuas an exclamation into the text. Ironically,sacrebleuas a minced oath dropped largely out of use in French in the mid-1900s. But, that hasn’t stopped Anglophone writers from using it as a mark of stereotypical Frenchness.
You might even say that an English-speaker who says sacrebleu is a …