'Votre effronterie m'étonne, fulminated Frederick in a furious note, when he suddenly discovered that all Europe was ringing with the absurdity of the man whom he had chosen to be the President of his favourite Academy, whose cause he had publicly espoused, and whom he had privately assured of his royal protection. 'Ah!
The word effrontery, which comes to us from the French effronterie, is really the same expression as the vulgar terms face and cheek, meaning "impudence." For the word comes from the Latin frons, "the forehead." An example of a word which was quite good English, and then came to be used as slang in a special sense, and then in this same special sense became good English again, is grit.