about-turn
noun [ C ] UK uk/əˌbaʊtˈtɜːn/ us/əˌbaʊtˈtɝːn/ (US about-face)
（朝反方向的）倒转
a change of direction
I'd only gone a little way down the street when I remembered I hadn't locked the door, so I made/did a quick about-turn. 我在街上刚走出不远就想起来忘锁门了，于是马上转身跑回去。
（意见或行为的）彻底转变
a complete change of opinion or behaviour
This is the government's second about-turn on the issue. 这是政府在这个问题上立场第二次180度大转变。