volte-face
/ˌvɒltəˈfɑːs/noun
1- an act of turning round so as to face in the opposite direction向后转; 大转弯。
1.1
- an abrupt and complete reversal of attitude, opinion, or position（态度、意见或立场的）突然完全改变, 大转变：
a remarkable volte-face on taxes.
税收上的大突变。
词源
early 19th cent.: from French， from Italian voltafaccia, based on Latin volvere 'to roll' + facies 'appearance， face'.