What does fluid mean?

Definitions for fluid
ˈflu ɪdflu·id

This dictionary definitions page includes all the possible meanings, example usage and translations of the word fluid.

Princeton's WordNet

  1. fluidnoun

    a substance that is fluid at room temperature and pressure

  2. fluidadjective

    continuous amorphous matter that tends to flow and to conform to the outline of its container: a liquid or a gas

  3. fluid, unstableadjective

    subject to change; variable

    "a fluid situation fraught with uncertainty"; "everything was unstable following the coup"

  4. fluid, runnyadjective

    characteristic of a fluid; capable of flowing and easily changing shape

  5. fluent, fluid, liquid, smoothadjective

    smooth and unconstrained in movement

    "a long, smooth stride"; "the fluid motion of a cat"; "the liquid grace of a ballerina"

  6. fluid, liquidadjective

    in cash or easily convertible to cash

    "liquid (or fluid) assets"

  7. fluid, mobileadjective

    affording change (especially in social status)

    "Britain is not a truly fluid society"; "upwardly mobile"


  1. fluidnoun

    Any substance which can flow with relative ease, tends to assume the shape of its container, and obeys Bernoulli's principle; a liquid, gas or plasma

  2. fluidadjective

    Of, or relating to fluid.

  3. fluidadjective

    In a state of flux; subject to change.

  4. fluidadjective

    Moving smoothly, or giving the impression of a liquid in motion.

  5. fluidadjective

    Convertible into cash.

Samuel Johnson's Dictionary

  1. FLUIDadjective

    Having parts easily separable; not solid.

    Etymology: fluidus, Latin; fluide, French.

    Or serve they as a flow’ry verge to bind
    The fluid skirts of that same wat’ry cloud,
    Lest it again dissolve, and show’r the earth? John Milton, P. Lost.

    If particles slip easily, and are of a fit size to be agitated by heat, and the heat is big enough to keep them in agitation, the body is fluid; and if it be apt to stick to things, it is humid. Isaac Newton, Opt.

  2. Fluidnoun

    In physick. Any animal juice: as the blood.

    Consider how luxury hath introduced new diseases, and with them, not improbably, altered the whole course of the fluids. Scriblerus Club , Mart. Scriblerus.


  1. Fluid

    In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, or external force. Fluids are a phase of matter and include liquids, gases and plasmas. They are substances with zero shear modulus, or, in simpler terms, substances which cannot resist any shear force applied to them. Although the term "fluid" includes both the liquid and gas phases, in common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. This colloquial usage of the term is also common in medicine and in nutrition ("take plenty of fluids"). Liquids form a free surface (that is, a surface not created by the container) while gases do not. Viscoelastic fluids like Silly Putty appear to behave similar to a solid when a sudden force is applied. Also substances with a very high viscosity such as pitch appear to behave like a solid (see pitch drop experiment).


  1. fluid

    A fluid is a substance that continually flows under an applied shear stress, or external force. Fluids can be a gas or a liquid and are characterized by their ability to freely change shape and yields easily to external pressure, as they have no definite shape but takes on the shape of their container.

Webster Dictionary

  1. Fluidadjective

    having particles which easily move and change their relative position without a separation of the mass, and which easily yield to pressure; capable of flowing; liquid or gaseous

  2. Fluidnoun

    a fluid substance; a body whose particles move easily among themselves

  3. Etymology: [L. fluidus, fr. fluere to flow: cf. F. fluide. See Fluent.]


  1. Fluid

    In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a super set of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids. Although the term "fluid" includes both the liquid and gas phases, in common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. For example, "brake fluid" is hydraulic oil and will not perform its required function if there is gas in it. This colloquial usage of the term is also common in medicine and in nutrition. Liquids form a free surface while gases do not. The distinction between solids and fluid is not entirely obvious. The distinction is made by evaluating the viscosity of the substance. Silly Putty can be considered to behave like a solid or a fluid, depending on the time period over which it is observed. It is best described as a viscoelastic fluid. There are many examples of substances proving difficult to classify. A particularly interesting one is pitch, as demonstrated in the pitch drop experiment currently running at the University of Queensland.

Chambers 20th Century Dictionary

  1. Fluid

    flōō′id, adj. that flows, as water: liquid or gaseous.—n. a substance in which the particles can move about with greater or less freedom from one part of the body to another.—adjs. Flu′idal; Fluid′ic; Fluid′iform.—vs.t. Fluid′ify, Flu′idise, to make fluid.—ns. Flu′idism; Fluid′ity, Flu′idness, a liquid or gaseous state.—adv. Flu′idly. [Fr.,—L. fluidus, fluid—fluĕre, to flow.]


  1. Fluid

    Fluid Inc. " the digital shopping innovator, designs and builds digital shopping experiences that brings brands to life, making the shopping experience fun, vivid, intuitive and social. In addition to design and development services, Fluid™s offering includes the Fluid Retail interactive merchandising suite which enables engaging customer experiences that drive conversion, customer satisfaction, and brand loyalty. Fluid™s customers range from mass-market retailers to luxury goods manufacturers, and include top brands such as: Sears, Benefit Cosmetics, Elie Tahari, Diapers.com, Nine West, Reebok, The North Face, and Vans. For more information, visit www.fluid.com, and follow us on Twitter @Fluid or Facebook FluidInc.

Editors Contribution

  1. fluid

    A specific form of matter.

    Blood in the human body is a form of fluid

    Submitted by MaryC on June 22, 2020  

  2. fluid

    Having a consistency that moves easily.

    The milk was fluid.

    Submitted by MaryC on December 22, 2019  

  3. fluid

    Matter in a liquid form.

    We can buy lighter fluid or other oils in a fluid form.

    Submitted by MaryC on December 22, 2019  

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British National Corpus

  1. Nouns Frequency

    Rank popularity for the word 'fluid' in Nouns Frequency: #1917

How to pronounce fluid?

How to say fluid in sign language?


  1. Chaldean Numerology

    The numerical value of fluid in Chaldean Numerology is: 4

  2. Pythagorean Numerology

    The numerical value of fluid in Pythagorean Numerology is: 7

Examples of fluid in a Sentence

  1. Casey Sommerfeld:

    This immune response can lead to increased inflammation and' leaky' blood vessels, which can lead to fluid accumulation in the lungs.

  2. Jakob Kern:

    The situation is quite volatile and fluid in northern Aleppo with families on the move seeking safety, we are extremely concerned as access and supply routes from the north to eastern Aleppo city and surrounding areas are now cut off, but we are making every effort to get enough food in place for all those in need, bringing it in through the remaining open border crossing point from Turkey.

  3. Mohamed Dagane:

    There is no confirmed cholera fatality at the hospital, we have sufficient stock of medicine and rehydration fluid to cater for any patient.

  4. Elizabeth Ayres:

    Miles 13 through to 18 were horrendous ! We were sprayed with cleaning fluid and water from the clean-up vehicles.

  5. Britt Slabinski:

    When we landed on top of the mountain, my helicopter took rocket-propelled grenade fire right away, bullets the size of your finger passing through there, those are the ones that hit hydraulic fluid, which ultimately took us out of the sky.

Popularity rank by frequency of use


Translations for fluid

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    make uniform
    • A. aberrate
    • B. excogitate
    • C. knead
    • D. flub

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