hydraulic

Etymology

It is borrowed from Latin hydraulicus,^[2][3][4][5] probably by way of, or under the influence of, Middle French hydraulique;^[6][7][8] the Shorter Oxford dates the French word to the 15th century.^[9] The Latin adjective is from Ancient Greek ὑδραυλικός (hudraulikós),^[2][3][6] from ὕδραυλις (húdraulis, “water organ”),^[10][6][3] formed from ὕδωρ (húdōr, “water”), stem ὑδρ- (hudr-), and αὐλός (aulós, “pipe, flute”).^[2][10][3] In Greek the adjective named a musical instrument worked by water, the water organ,^[2][6] which Etymonline credits to the Egyptian Ctesibius;^[8] Latin authors such as Vitruvius first extended the word to other water machines.^[2] Etymonline derives húdōr from Proto-Indo-European *wed- (“water; wet”),^[8] and Klein relates aulós to Latin alveus (“a hollow, cavity”).^[10]

Earliest recorded meaning

As a noun, a water organ, an instrument that used the pressure of water to compress air: 1626, in Francis Bacon's Sylva Sylvarum.^[2][6] Barnhart's Concise dictionary dates the adjective to 1606,^[7] Etymonline to about 1600,^[8] and the full Barnhart to 1656, in Blount's Glossographia, where it was applied to machines worked by water.^[6][2]

Semantic evolution

The word moved from the water organ to water engines and machines in general, as it had already in Latin.^[2][8] From 1661 it meant relating to water or another liquid carried through pipes or channels.^[2][5] The noun hydraulics, for the science of liquids in motion, appears in 1671, in Boyle, formed like mathematics.^[6][7] From 1829 the adjective was used of cements and limes that harden under water,^[2][11] and since 1941 of the fluid used in hydraulic brakes and other equipment.^[2] An American verb, to work a mine by jets of water, is recorded from 1868.^[2][5] In Australian slang, Hydraulic Jack was a nickname for a light-fingered person, a pun on the hydraulic jack that will "lift anything".^[12]

Timeline

• 1626 – noun, a water organ (obsolete by 1661).^[2][6]
• 1656 – of machines worked by water.^[2][6]
• 1661 – relating to water conveyed through pipes.^[2][5]
• 1671 – hydraulics.^[6]
• 1729 – noun, a hydraulic engine or press.^[2]
• 1829 – of cement or lime, hardening under water.^[2]
• 1868 – verb, to work by hydraulic mining.^[2]
• 1941 – of a fluid, used in hydraulic equipment.^[2]

Modern meaning

Adjective

1. Operated by the pressure of a liquid, such as water or oil, forced through pipes: hydraulic brakes.
2. Relating to liquids in motion, or to hydraulics.
3. Of cement or lime, hardening under water.

Noun

1. A hydraulic machine or system.

Verb

1. (mining) To work or excavate with a powerful jet of water.

Word family

• hydraulically
• electrohydraulic
• nonhydraulic
• hydraulic press
• hydraulic cement
• hydraulic radius
• hydraulic fluid

Related words

• hydraulics
• hydro-
• water
• alveolus
• hydrant

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
4. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
5. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b c d e f g h i j Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ a b c Barnhart, Robert K., ed. (1995), The Barnhart Concise Dictionary of Etymology, New York: HarperCollins
8. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
9. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
10. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
11. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
12. ^ Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com