hydraulic

American  

[hahy-draw-lik, -drol-ik] / haɪˈdrɔ lɪk, -ˈdrɒl ɪk /

adjective

1. operated by, moved by, or employing water or other liquids in motion.

2. operated by the pressure created by forcing water, oil, or another liquid through a comparatively narrow pipe or orifice.

3. of or relating to water or other liquids in motion.

4. of or relating to hydraulics.

5. hardening under water, as a cement.

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hydraulic British  

/ haɪˈdrɒlɪk /

adjective

1. operated by pressure transmitted through a pipe by a liquid, such as water or oil

2. of, concerned with, or employing liquids in motion

3. of or concerned with hydraulics

4. hardening under water

   hydraulic cement

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hydraulic Scientific  

/ hī-drô′lĭk /

1. Operated by the pressure of water or other liquids. Hydraulic systems, such as hydraulic brakes, allow mechanical force to be transferred along curved paths (through pipes or tubes) that would be difficult for solid mechanisms, such as levers or cables, to negotiate efficiently.

2. Relating to hydraulics.

3. Capable of hardening under water, as cement.

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hydraulic Cultural  

1. A descriptive term for a system operated or moved by a fluid. The hydraulic jack, in which force is transmitted from a handle by means of a heavy oil, is probably the most familiar hydraulic device.

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Other Word Forms

• nonhydraulic
  adjective
• unhydraulic
  adjective
• hydraulically
  adverb

Etymology

Origin of hydraulic

1620–30; < Latin hydraulicus < Greek hydraulikós of a water organ. See hydraulus, -ic

Explanation

The adjective hydraulic refers to a process using pressurized water or other fluid to generate great mechanical power, without the wear and tear of gears or levers. Hydraulic systems are popular for use in heavy-duty machinery. It might seem odd that the original Greek word hydraulikós from which hydraulic comes referred to water (hydra) and also to a musical instrument made from a hollow tube (aulos). You might ask, "What's a musical instrument got to do with hydraulics?" Well, you can see the connection when you know that something that's hydraulic means it is operated through the pressure of water or liquid through a pipe or hose, easily generating great force (instead of music).

Example Sentences

See Examples For:

hydraulic

His Mercedes suffered a hydraulic leak halfway through the first session and the car was not ready for him to go back out on track until halfway through the second session.

From BBC ● Sep. 25, 2026

“This decision will result in carriers that are enabled by battle-tested steam and hydraulic systems that are more resilient and robust than the present, more exquisite, follow-on systems,” the White House said in a statement.

From The Wall Street Journal ● Aug. 13, 2026

Firefighters worked for nearly two hours to extricate the driver, using hydraulic tools to cut into the trapped flatbed’s cab.

From Los Angeles Times ● Jul. 31, 2026

Burning natural gas also causes significant air pollution in the form of nitric oxides, sulfur, mercury and particulates, while hydraulic fracturing or "fracking," can contaminate ground water supplies.

From Barron's ● Jul. 25, 2026

When she reached the hydraulic doors, she heard him behind her.

From "A Thousand Splendid Suns" by Khaled Hosseini