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fluid

Etymology and origin of the English word fluid

History Permalink
Confidence
Established
Formation
Borrowing
First attested
before 1425
Borrowed from
Middle French fluide
Ultimate origin
Latin (fluo)
Etymology tree
inherited borrowed derived
Latin fluidus
English fluid

Pronunciation

  • IPA: /ˈfluːɪd/ (UK); /ˈflu.ɪd/ (US)[1]

Etymology

It is borrowed from Middle French fluide or directly borrowed from Latin fluidus (“flowing, moist”),[2][3][4] from fluere (“to flow”) (see fluent).[2][3][5]

Earliest recorded meaning

Liquid, capable of flowing: probably before 1425, in a translation of Chauliac's Grande Chirurgie;[2][3] the OED's first example is from 1603.[6]

Semantic evolution

Figuratively, not fixed or rigid, of non-material things, it is from the 1640s, 1642 in the OED.[3][6] Of speech, flowing easily, it is from 1691.[6] The noun, a substance whose particles move freely, a liquid or gas, is from 1661, in Robert Boyle's treatise on air.[2][3][6] A liquid of the body or a plant is from 1704.[6] In older physics, electricity and magnetism were thought of as subtle fluids (1750).[6] Fluidity is from 1603, in Florio's Montaigne.[2]

Timeline

  • before 1425 – flowing, liquid.[2]
  • 1603 – fluidity.[2]
  • 1642 – not rigid, figuratively.[6]
  • 1661 – the noun, in Boyle.[2][6]
  • 1704 – a body fluid.[6]

Modern meaning

Noun

  1. A substance, such as a liquid or gas, that flows and takes the shape of its container.

Adjective

  1. Able to flow easily; not solid.
  2. Smooth and graceful: fluid movements.
  3. Not fixed; likely to change: a fluid situation.

Word family

  • fluidity
  • fluidly
  • fluidness
  • fluidal
  • fluidally
  • fluidlike
  • superfluid
  • nonfluid
  • fluctuate
  • fluctuation
  • fluency
  • fluent
  • flux
  • fluidic
  • fluidics
  • fluidize
  • semifluid
  • influence
  • superfluous

References

  1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  4. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  5. ^ Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  6. ^ a b c d e f g h i Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press

Related etymologies

Cite this entry

“Fluid.” Etymologically, 16 Oct. 2026, etymologically.com/en/fluid. Accessed 16 Oct. 2026.

Last edited on . ·