[T]he ancient Greeks & Romans knew what speed was, & yet no-one supposes they called it speed, whence it follows that speedo- & speedometer are barbarisms. [Fowler]
The correct classical formation is tachometer.speed-,速度,-meter,仪器。 speed-read 快速阅读
该词的英语词源请访问找单词词源英文版:speedometer 词源,speedometer 含义。