The meaning of FLUID is having particles that easily move and change their relative position without a separation of the mass and that easily yield to pressure : capable of flowing.

Although the term fluid generally includes both the liquid and gas phases, its definition varies among branches of science. Definitions of solid vary as well, and depending on field, some substances can …

FLUID definition: 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. See examples of fluid used in …

fluid adjective (LIKELY TO CHANGE) If situations, ideas, or plans are fluid, they are not fixed and are likely to change, often repeatedly and unexpectedly:

Aug 7, 2021 · Learn what a fluid is in physics and other sciences. Get the definition and see examples of fluids in everyday life.

Jan 14, 2026 · fluid (countable and uncountable, plural fluids) 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 …

A situation that is fluid is unstable and is likely to change often. The situation is extremely fluid and it can be changing from day to day.

adj. Hydraulics pertaining to a substance that easily changes its shape; capable of flowing. Hydraulics consisting of or pertaining to fluids. changing readily; shifting; not fixed, stable, or rigid: fluid …

Section Summary A fluid is a state of matter that yields to sideways or shearing forces. Liquids and gases are both fluids. Fluid statics is the physics of stationary fluids.

Synonyms for FLUID: liquid, flowing, thin, fluent, diluted, weak, semisolid, watery; Antonyms of FLUID: solid, nonliquid, hard, gelatinous, thick, coagulated, clotted, viscous