When the engine of a vehicle revs, or when you rev it, the engine speed is increased as the accelerator is pressed.
例句
The engine started, revved and the car jerked away down the hill...引擎發動了，油門加大后車沖下了山坡。The old bus was revving its engine, ready to start the journey back towards Madrid.這輛舊巴士發動了引擎，準備啟程返回馬德里。
N-PLURAL
(發動機的)轉速
If you talk about the revs of an engine, you are referring to its speed, which is measured in revolutions per minute.
例句
The engine delivers instant acceleration whatever the revs.不論轉速如何，發動機都可以立即加速。