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.

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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

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Etymology

Origin of hydraulic ram

First recorded in 1800–10

Example Sentences

“Approaching the northeast coast of Flinders Island in eastern Bass Strait she suffered damage to the hydraulic ram that adjusts the angle of the canting or swinging keel beneath the hull,” the spokesman said.

From Washington Times • Dec. 27, 2016

In weeks to come, a hydraulic ram will rack the tail to one side.

From BusinessWeek • Feb. 13, 2014

The stern, part of the bench and all, lifts on a hydraulic ram to reveal the engine room, which, I must say, is neatly organized.

From Time Magazine Archive

Her essential part is a vertical hydraulic ram that carries a subcritical mass of fissionable material surrounded by a casing of neutron-reflecting material.

From Time Magazine Archive

In 1797 he took out a patent in connexion with raising water on the principle of the hydraulic ram.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 3 "Borgia, Lucrezia" to "Bradford, John" by Various