The definition of hydraulic is operated by the moving force of a liquid.(adjective)
An example of a hydraulic machine is one that is powered by water.
See hydraulic in Webster's New World College Dictionary
Origin: Fr hydraulique < L hydraulicus < Gr hydraulikos, of a water organ < hydraulis, water organ < hydōr, water + aulos, tube, pipe < IE base *aulos > (with metathesis) L alvus, the belly
See hydraulic in American Heritage Dictionary 4
Origin: Latin hydraulicus
Origin: , from Greek hudraulikos
Origin: , from hudraulis, water organ
Origin: : hudro-, hudr-, hydro-
Origin: + aulos, pipe, flute.
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