a substance, as a liquid or gas, that is capable of flowing and that changes its shape at a steady rate when acted upon by a force tending to change its shape.
adjective
pertaining to a substance that easily changes its shape; capable of flowing.
consisting of or pertaining to fluids.
changing readily; shifting; not fixed, stable, or rigid: fluid movements.
convertible into cash: fluid assets.
Origin of fluid
First recorded in 1595–1605; from Latin fluidus, equivalent to flu(ere) “to flow” + -idus adjective suffix; see -id4
They cited a fluid-dynamics simulation that showed a “massive upward transport of virus aerosol particles” during flushing, leading to large-scale virus spread indoors.
Scientists found coronavirus in a long-vacant apartment. A possible spreader? ‘Fecal aerosol plumes’|Claire Zillman, reporter|August 27, 2020|Fortune
That’s because, he says, T-cell assays require a more complex blood sample that preserves both the serum—or fluid part of blood—and the individual blood cells.
Scientists to Wall Street: You don’t really understand how COVID vaccine tests work|Jeremy Kahn|August 24, 2020|Fortune
These narratives underscore the fluid and transnational histories of diseases, their impact and possible cure.
Science Fiction Explores the Interconnectedness Revealed by the Coronavirus Pandemic|Mayurika Chakravorty|August 9, 2020|Singularity Hub
Kidneys clean our blood using nephrons, which are essentially filters that let fluid and waste products through while blocking blood cells, proteins, and minerals.
Artificial Kidneys Are a Step Closer With This New Tech|Vanessa Bates Ramirez|June 3, 2020|Singularity Hub
The rotating flow maintains a shape where the center looks sunken as the fluid gets pushed to the outer edge.
Climb like a slo-mo Spiderman using this super suction robot|Carolyn Wilke|May 12, 2020|Science News For Students
So we know that boring down to the bedrock and pumping it full of fluid can cause earthquakes.
26 Earthquakes Later, Fracking’s Smoking Gun Is in Texas|James Joiner|January 7, 2015|DAILY BEAST
Underneath minimalistic names like Detox and Cleanse, enticing descriptions of the fluid medicine bags help narrow the choices.
The I.V. Doc Comes to Your House, Fights Hangovers, and Wins|Abby Haglage|July 20, 2014|DAILY BEAST
Kids are less likely to drink appropriate amounts of fluid in preparation of and participation in physical activity.
A Lesson From LeBron James’ Game One Nightmare|Dr. Anand Veeravagu, MD, Tej Azad|June 7, 2014|DAILY BEAST
Yet he is a skilled communicator, and politics is a fluid environment, so anything is possible.
Joe Scarborough: ‘No Plans’ to Run for President|Lloyd Grove|March 17, 2014|DAILY BEAST
Of course, the situation in Ukraine is fluid, and the intelligence coming from the area is incomplete.
Russia's Special Ops Invasion of Ukraine Has Begun|Eli Lake, Anna Nemtsova|March 15, 2014|DAILY BEAST
When fluid has collected in the lower part of the chest cavity the sound will also be dull on percussion.
Special Report on Diseases of Cattle|U.S. Department of Agriculture
In one case the fluid would not flow in, and only distended the veins of the arm injected.
A System of Practical Medicine by American Authors, Vol. I|Various
That universe is fluid and fluent; its contents dissolve and re-form with amazing rapidity.
The Child and the Curriculum|John Dewey
With it crystallization is not the mysterious act itself by which a substance passes from the fluid state to the solid state.
Amiel's Journal|Henri-Frdric Amiel
Another important method consists in inoculating an animal with some fluid containing the various bacteria.
Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2|Various
British Dictionary definitions for fluid
fluid
/ (ˈfluːɪd) /
noun
a substance, such as a liquid or gas, that can flow, has no fixed shape, and offers little resistance to an external stress
A state of matter, such as liquid or gas, in which the component particles (generally molecules) can move past one another. Fluids flow easily and conform to the shape of their containers. See also state of matterviscosity.