hydraulic ram

American  

noun

1. a device by which the energy of descending water is utilized to raise a part of the water to a height greater than that of the source.

---

hydraulic ram British  

noun

1. any large device involving the displacement of a piston or plunger driven by fluid pressure

2. a form of water pump utilizing the kinetic energy of running water to provide static pressure to raise water to a reservoir higher than the source

---

Etymology

Origin of hydraulic ram

First recorded in 1800–10

Example Sentences

The cockpit holding the driver is lifted on hydraulic rams to simulate precisely how a car corners.

From BBC

It comes complete with pilot's visor and internal hydraulic rams for its operation.

From BBC

In 1997, a British female police officer was stabbed and killed while using a hydraulic ram to enter a flat.

From The Guardian

Weighing 4,000 tonnes, it has 100m of trailing infrastructure that enables workers to install the tunnel walls as the cutting head inches forward powered by hydraulic rams.

From BBC

For their test firing, the researchers used a hydraulic ram to drive the cylinder into a preheated engine.

From Economist