to unmask, make an about face, reverse a decision ☊ 
lật mặt ☊ (1) boisterous, hostile, rebellious, contrary, opposite, reverse (2) to play with, tamper with, mess with ☊
nghịch ☊ in the opposite direction, in reverse order, contrariwise ☊ ngược chiều ☊ to turn 180 degrees, completely reverse oneself ☊ quay 180 độ ☊ counter slope, reverse slope ☊ sườn đối đỉnh ☊