fluid

/ˈfluɪd/

/ˈfluɪd/

Other forms: fluids; fluidly

Something that is unstable or subject to change can be described as fluid. The fluid political situation in a particular country makes it unsafe to travel there, with the constant possibility of a violent uprising.

A liquid is a fluid — something that flows easily when poured — although gases can also be called fluid. When your doctor told you to drink lots of fluids to help your cold symptoms, she probably meant things like water or orange juice, not root beer floats. If a movement is smooth, it can also be described as fluid. You have to make fluid arm movements in ballet so you look graceful.

Definitions of fluid

1. noun

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

   gas

   a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely

   liquid

   fluid matter having no fixed shape but a fixed volume

   atmosphere

   the envelope of gases surrounding any celestial body

   argonon, inert gas, noble gas

   any of the chemically inert gaseous elements of the helium group in the periodic table

   Cl, atomic number 17, chlorine

   a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)

   F, atomic number 9, fluorine

   a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite

   H, atomic number 1, hydrogen

   a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe

   N, atomic number 7, nitrogen

   a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues

   O, atomic number 8, oxygen

   a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust

   butane

   occurs in natural gas; used in the manufacture of rubber and fuels

   propane

   colorless gas found in natural gas and petroleum; used as a fuel

   afterdamp

   a toxic mixture of gases (including carbon dioxide and carbon monoxide and nitrogen) after an explosion of firedamp in a mine

   firedamp

   a mixture of gases (mostly methane) that form in coal mines and become explosive when mixed with air

   arsine

   a poisonous colorless flammable gas used in organic synthesis and to dope transistors and as a poison gas in warfare

   nitrogen dioxide

   a highly poisonous brown gas (NO2)

   nitric oxide

   a poisonous red-brown gas (NO)

   artificial blood

   a liquid that can carry large amounts of oxygen and can serve as a temporary substitute for blood

   blow gas, blowing gas

   the gas leaving a generator during a blow period

   butene, butylene

   any of three isomeric hydrocarbons C4H8; all used in making synthetic rubbers

   cyanogen

   a colorless toxic gas with a pungent almond odor; has been used in chemical warfare

   exhaust, exhaust fumes, fumes

   gases ejected from an engine as waste products

   elixir

   a sweet flavored liquid (usually containing a small amount of alcohol) used in compounding medicines to be taken by mouth in order to mask an unpleasant taste

   air

   a mixture of gases (especially oxygen) required for breathing; the stuff that the wind consists of

   compressed gas

   gas at a high pressure that can be used as a propellant

   H2O, water

   binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent

   ethene, ethylene

   a flammable colorless gaseous alkene; obtained from petroleum and natural gas and used in manufacturing many other chemicals; sometimes used as an anesthetic

   extravasation

   an extravasated liquid (blood or lymph or urine); the product of extravasation

   air gas, producer gas

   a gas made of carbon monoxide and hydrogen and nitrogen; made by passing air over hot coke

   formaldehyde, methanal

   a colorless poisonous gas; made by the oxidation of methanol

   greenhouse emission, greenhouse gas

   a substance in the air that warms a planet by trapping heat

   bottled gas, liquefied petroleum gas

   hydrocarbon gases, usually propane or butane, kept under pressure

   water gas

   a mixture of hydrogen and carbon monoxide with small amounts of other gases; made by blowing steam over hot coke or coal

   ideal gas, perfect gas

   a hypothetical gas with molecules of negligible size that exert no intermolecular forces

   inhalant

   something that is inhaled

   instillation

   a liquid that is instilled drop by drop

   liquid crystal

   a liquid exhibiting properties of a crystal that are not shown by ordinary liquids

   methane

   a colorless, odorless gas used as a fuel

   ozone

   a colorless gas (O3) soluble in alkalis and cold water; a strong oxidizing agent; can be produced by electric discharge in oxygen or by the action of ultraviolet radiation on oxygen in the stratosphere (where it acts as a screen for ultraviolet radiation)

   phosgene

   a colorless poisonous gas that smells like new-mown hay; used in chemical warfare

   phosphine

   a colorless gas with a strong fishy smell; used as a pesticide

   poison gas

   a gas that is poisonous to breath or contact; used in chemical warfare

   propene, propylene

   a flammable gas obtained by cracking petroleum; used in organic synthesis

   mephitis

   a poisonous or foul smelling gas emitted from the earth

   sewer gas

   foul-smelling gas that forms in sewers

   spill

   liquid that is spilled

   sublimate

   the product of vaporization of a solid

   sulfur dioxide, sulphur dioxide

   a colorless toxic gas (SO2) that occurs in the gases from volcanoes; used in many manufacturing processes and present in industrial emissions; causes acid rain

   lachrymator, lacrimator, tear gas, teargas

   a gas that makes the eyes fill with tears but does not damage them; used in dispersing crowds

   tuberculin

   a sterile liquid containing a purified protein derivative of the tuberculosis bacterium; used in the diagnosis of tuberculosis

   type of:

   matter

   that which has mass and occupies space
2. noun

   a substance that is fluid at room temperature and pressure
   types:

   coolant

   a fluid agent (gas or liquid) that produces cooling; especially one used to cool a system by transferring heat away from one part to another

   filtrate

   the product of filtration; a gas or liquid that has been passed through a filter

   ichor

   (Greek mythology) the rarified fluid said to flow in the veins of the Gods

   liquid

   a substance that is liquid at room temperature and pressure

   beverage, drink, drinkable, potable

   any liquid suitable for drinking

   water

   a liquid necessary for the life of most animals and plants

   supernatant

   the clear liquid that lies above a sediment or precipitate

   alcohol

   any of a series of volatile hydroxyl compounds that are made from hydrocarbons by distillation

   ammonia, ammonia water, ammonium hydroxide

   a water solution of ammonia

   antifreeze

   a liquid added to the water in a cooling system to lower its freezing point

   distillate, distillation

   a purified liquid produced by condensation from a vapor during distilling; the product of distilling

   pyroligneous acid, wood vinegar

   a red-brown liquid formed in distillation of wood which contains acetic acid, methanol, acetone, wood oils, and tars

   medium

   a liquid with which pigment is mixed by a painter

   ink

   a liquid used for printing or writing or drawing

   grume

   a thick viscous liquid

   liquor

   a liquid substance that is a solution (or emulsion or suspension) used or obtained in an industrial process

   percolate

   the product of percolation

   sheep dip

   a liquid mixture containing pesticides in which sheep are dipped to kill parasites

   snake oil

   (medicine) any of various liquids sold as medicine (as by a travelling medicine show) but medically worthless

   type of:

   substance

   the real physical matter of which a person or thing consists
3. adjective

   characteristic of a fluid; capable of flowing and easily changing shape
   synonyms: runny

   liquid

   existing as or having characteristics of a liquid; especially tending to flow
4. adjective

   subject to change; variable
   “a fluid situation fraught with uncertainty”

   synonyms: unstable

   changeable, changeful

   such that alteration is possible; having a marked tendency to change
5. adjective

   affording change (especially in social status)
   “Britain is not a truly fluid society”

   synonyms: mobile

   changeable, changeful

   such that alteration is possible; having a marked tendency to change
6. adjective

   smooth and unconstrained in movement
   “the fluid motion of a cat”

   synonyms: fluent, liquid, smooth

   graceful

   characterized by beauty of movement, style, form, or execution
7. adjective

   in cash or easily convertible to cash
   “liquid (or fluid) assets”

   synonyms: liquid

   disposable

   free or available for use or disposition