The only other ship to match her was the Thermopylae.这里other

这是新概念英语3中的句子
加上前面一句完整的比较句式是：
The Cutty Sark was one of the fastest sailing ships that has ever been built.The only other ship to match her was the Thermopylae.
“卡蒂萨克”号是帆船制造史上速度最快的一艘帆船,唯一可以与之一比高低的另一艘是“塞姆皮雷”号帆船.
这是one .the other 句式

动词不定式to作定语，修饰the only other ship
other 其他的，另外的
翻译：唯一可以与之相比的是“塞莫皮莱”帆船。