1
: operated, moved, or effected by means of water
2
a
: of or relating to hydraulics
hydraulic engineer
b
: of or relating to water or other liquid in motion
hydraulic erosion
3
: operated by the resistance offered or the pressure transmitted when a quantity of liquid (such as water or oil) is forced through a comparatively small orifice or through a tube
hydraulic brakes
4
: hardening or setting under water
hydraulic cement

Did you know?

By means of a hydraulic lift, the driver can lift the bed of a dump truck with the touch of a button. He might also repair the hydraulic steering, the hydraulic brake, or the hydraulic clutch—all of which, like the lift that holds everything up, take advantage of the way liquids act under pressure. Somewhat like a pulley or a lever, a hydraulic system magnifies the effect of moderate pressure exerted over a longer distance into powerful energy for a shorter distance.

Examples of hydraulic in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Two other reports for 2026 were added in the past few days, MIOSHA said a 28-year-old landscaper in Southfield was working underneath a compact wheel loader to repair a hydraulic line on the vehicle on January 16. Paula Wethington, CBS News, 19 Aug. 2026 Authorities said equipment found at the ADU included hydraulic presses, cutting agents, personal protective equipment, scales and Narcan, a medication used to counteract the effects of opioids. Jason Green, Mercury News, 18 Aug. 2026 It’s all meant to defeat the crime rings that are often armed with nothing more than hydraulic bolt cutters, preying on railroads as a reliable source of easy-to-steal merchandise. Kiel Porter, Fortune, 17 Aug. 2026 Major upgrades include electromagnetic systems, such as arresting gear to catch landing aircraft safely and smoothly (replacing old hydraulic recovery systems) and electromagnetic linear motors rather than cables to move munitions. Maria Mocerino, Interesting Engineering, 16 Aug. 2026 See All Example Sentences for hydraulic

Word History

Etymology

Latin hydraulicus, from Greek hydraulikos, from hydraulis hydraulic organ, from hydr- + aulos reed instrument — more at alveolus

First Known Use

1661, in the meaning defined at sense 1

Time Traveler
The first known use of hydraulic was in 1661

Browse Nearby Words

Cite this Entry

“Hydraulic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydraulic. Accessed 25 Aug. 2026.

Kids Definition

hydraulic

adjective
1
: operated, moved, or brought about by means of water
2
: of or relating to hydraulics
hydraulic engineer
3
: operated by pressure transmitted when a quantity of liquid is forced through a small hole or through a tube
hydraulic brakes
4
: hardening or setting under water
hydraulic cement

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