《国语·晋语·史苏论献公伐骊戎胜而》
齿牙交对，就是交替取胜，所以我才说胜而不吉。
交捽，是交胜也，臣故云。
Teeth and gums are biting each other, which means that each party wins once after another. Therefore, I say that you will win but it is not auspicious.