sissy bar
[美国俚语](摩托车或自行车等的)倒U形靠背
参考例子
1.So my father took my old bike, slapped a new coat of paint on it, and equipped it with a banana seat, monkey handlebars and a sissy bar.
于是，我父亲把我的旧单车拿过去，仿照Sting-Ray的样子，涂了一层新漆，装了一个细长而后部翘起的车座、一个直把，座位后面还装了一根保护杠。
2.It didn't matter to me that some friends had new Sting-Rays straight from the Schwinn factory. Or even that my dad put the sissy bar on backward, which exposed me to some teasing before we fixed it.
我并不在乎有些朋友骑的是从Schwinn厂子刚出产的崭新Sting-Ray单车，也不在乎父亲把保护杠装反了，在重新装过之前我还受到了一些取笑。