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

The process of hydraulic fracturing ekes out oil from older wells, and involves cracking the bedrock several thousand feet below the seafloor by injecting chemical fluids with intense pressure.

From Los Angeles Times ● Aug. 14, 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

Materials arrive for the day in a succession of 18-wheeler trucks, which are tipped by hydraulic lifts to empty the contents of their trailers onto the 28,000-square-foot tipping room floor.

From Barron's ● Jun. 17, 2026

Hradecky suggests the RAT was, therefore, more likely triggered because both engines had already lost power and fallen below idle speed, rather than by a separate electrical or hydraulic failure.

From BBC ● Jun. 15, 2026

Nor was Galileo, when he invented the hydraulic press, working on some new, practical problem that only a competent engineer could tackle.

From "The Invention of Science" by David Wootton