hydraulic

adjective

hy·​drau·​lic hī-ˈdrȯ-lik 

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

hydraulically

hī-ˈdrȯ-li-k(ə-)lē 

adverb

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

The design process took more than five years, a negotiation between the city’s strict hydraulic requirements and the neighborhood’s shifting wishes; the result was something no one had pictured in advance. —Eric Klinenberg, New Yorker, 6 Apr. 2026

Supply and demand The United States has done remarkable work over the past decade and a half reshaping its energy industry, thanks to the advent of hydraulic fracking and horizontal drilling, particularly in Texas’ Permian Basin. —David Goldman, CNN Money, 6 Apr. 2026

Active suspension with hydraulic roll stabilization. —Tony Leopardo, Mercury News, 5 Apr. 2026

Manual systems back up their redundant hydraulic flight-control systems. —Tom Liddy, ABC News, 3 Apr. 2026

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

Phrases Containing hydraulic

• hydraulic fracturing

Rhymes for hydraulic

• bucolic
• carbolic
• embolic
• glycolic
• phenolic
• podzolic
• symbolic
• systolic
• alcoholic
• anabolic
• apostolic
• catabolic

Kids Definition

hydraulic

adjective

hy·​drau·​lic hī-ˈdrȯ-lik 

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

hydraulically

-ˈdrȯ-li-k(ə-)lē 

adverb