turbulence

Etymology

It is borrowed from Late Latin turbulentia (“trouble, disquiet”),^{[2][3][4][5][6]} from turbulentus (“full of commotion, restless, stormy”),^[2][3][4] from turba (“turmoil, crowd”) and turbō (“to disturb, agitate”).^[2] The OED compares Old French turbulance, also spelled with the ending ‑ence and recorded from the 14th century, as perhaps the immediate source,^[2] and the Shorter Oxford and the Oxford Dictionary of English also allow a French origin.^[7][8] The adjective turbulent has the same Latin source.^[3][2]

Earliest recorded meaning

Turbidity, cloudiness, of urine: before 1425, in Daniel's treatise on uroscopy.^[6] Etymonline also gives "turbidity, cloudiness" as the first sense, in the early 15th century.^[3]

Semantic evolution

The sense of a disturbed state, violent commotion or unruly conduct is recorded from the 1590s:^[3] the OED's first quotation is from Florio's Italian dictionary (1598),^[2] and Merriam-Webster dates it to 1595.^[5] From 1730, in Thomson's Winter, it was used of stormy natural conditions.^[2] The scientific sense, irregular eddying flow in a fluid, appears in 1907 in Lanchester's Aerodynamics,^[2] and the air eddies that buffet aircraft are called turbulence by 1918.^[3] In engineering the word was also used from 1923 for disturbance produced in an engine to speed up combustion.^[2] A rare variant is turbulency.^[3][9]

Timeline

• before 1425 – turbidity, cloudiness.^[6]
• 1595 – first known use of the sense of disorder, according to Merriam-Webster.^[5]
• 1598 – violent commotion, disturbance; unruly conduct.^[2]
• 1730 – stormy or tempestuous natural conditions.^[2]
• 1907 – irregular flow of a fluid.^[2]
• 1918 – air eddies that buffet aircraft.^[3]
• 1923 – disturbance in an engine to speed combustion.^[2]

Meanings

Noun

1. A state of confusion, agitation or disorder; violent commotion or unrest: the turbulence of the years after the revolution.^[9][5][2]
2. Irregular, eddying motion in a liquid or gas, as opposed to smooth flow.^[9][2]
3. Local instability of the atmosphere, oceans or rivers; especially, disturbed air that jolts an aircraft.^[9][3]
4. Stormy or violent natural conditions.^[2][5]

Word family

• clear-air turbulence

Related words

• turbulent
• turbid
• disturb
• perturb

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 Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g h i Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
5. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b c Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
7. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
8. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
9. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins