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adj Uncommon

hydraulic

heye-DRO-lihk

Hydraulic (adj) means Operated by the pressure of a liquid moving through pipes or cylinders. Example: “The digger's bucket is raised and lowered by a hydraulic arm.”

adj
1
Operated by the pressure of a liquid moving through pipes or cylinders.
"The digger's bucket is raised and lowered by a hydraulic arm."

How to use hydraulic

Learner’s notes

In plain EnglishPowered by liquid pressure pushed through pipes, rather than by electricity or plain mechanics.

Common pairings
hydraulic brakes hydraulic press hydraulic lift

Word forms

hydraulicked past tense, hydraulics singular

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Test yourself on “hydraulic” A quick quiz — meaning, synonyms & usage

Fill the gap

Can you complete this real example?

The digger's bucket is raised and lowered by a _____ arm.

Etymology

From Greek hydraulikos, describing a "water organ" — an ancient musical instrument powered by water pressure — built from hydor ("water") and aulos ("pipe").

Origin: Greek

fluid-powered liquid-driven

Frequently asked questions

What does “hydraulic” mean?

The word “hydraulic” means operated by the pressure of a liquid moving through pipes or cylinders. In plain terms, powered by liquid pressure pushed through pipes, rather than by electricity or plain mechanics.

How do you pronounce “hydraulic”?

“Hydraulic” is pronounced heye-DRO-lihk (/haɪˈdɹɔːlɪk/ in IPA).

How do you use “hydraulic” in a sentence?

Here is “hydraulic” used in a sentence: “The digger's bucket is raised and lowered by a hydraulic arm.”

What part of speech is “hydraulic”?

“Hydraulic” is an adjective.

Where does the word “hydraulic” come from?

The word “hydraulic” comes from Greek. From Greek hydraulikos, describing a "water organ" — an ancient musical instrument powered by water pressure — built from hydor ("water") and aulos ("pipe").

Is “hydraulic” a common word?

“Hydraulic” is an uncommon word in modern English.

What is the difference between "hydraulic" and "pneumatic"?

"Hydraulic" systems are operated by the pressure of a liquid moving through pipes or cylinders, while pneumatic systems use compressed air or gas instead of liquid. Both transmit force through pressurized fluid, but the type of fluid used is the key distinction.

What kinds of equipment commonly use hydraulic power?

Hydraulic power is common in heavy machinery such as excavators, car brakes, lifts, and industrial presses, all of which rely on liquid pressure through pipes or cylinders to generate force. This makes "hydraulic" a frequent term in engineering and automotive contexts.

Why is liquid used in hydraulic systems instead of air?

Liquids are essentially incompressible, which allows hydraulic systems to transmit force efficiently and precisely through pipes or cylinders under pressure. This is a key reason hydraulic systems are favored for heavy-duty applications requiring strong, controlled force.

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