mode about-face模转换
signal about-face信号变换
angle about-face挂钩开关
red about-face红移
depth about-face深度转换
about-face aeon转化期
about-face arrangement匝数比
thermal about-face热漂移
about-face on接通
N-COUNT（可数名词） An about-face is a complete change of attitude or opinion. 彻底改变
Few observers believe the president will do an about-face and start spending more.
没有几个观察家认为总统将做出彻底改变并开始增加支出。