WordReference Random House Learner's Dictionary of American English © 2026flu•id /ˈfluɪd/USA pronunciation
n.
- Hydraulics, Physicsa substance, such as a liquid or gas, that is capable of flowing and that changes its shape when acted upon by a force: [uncountable]Fluid dripped from the tank.[countable]to drink fluids.
adj.
- Hydraulicsflowing or capable of flowing:a fluid substance.
- changing easily or readily; not fixed, stable, or rigid:Our plans are fluid.
- smooth and flowing:a dancer with fluid gestures.
- Businessconvertible into cash;
liquid:fluid assets.
flu•id•i•ty /fluˈɪdɪti/USA pronunciation n. [uncountable]
flu•id•ly, adv. See -flu-.
WordReference Random House Unabridged Dictionary of American English © 2026flu•id
(flo̅o̅′id),USA pronunciation n.
- Hydraulics, Physicsa 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.
adj.
- Hydraulicspertaining to a substance that easily changes its shape;
capable of flowing.
- Hydraulicsconsisting of or pertaining to fluids.
- changing readily;
shifting;
not fixed, stable, or rigid:fluid movements.
- convertible into cash:fluid assets.
- Latin fluidus, equivalent. to flu(ere) to flow + -idus -id4
- 1595–1605
flu′id•al, adj.
flu′id•ly, flu′id•al•ly, adv.
flu′id•ness, n.
Collins Concise English Dictionary © HarperCollins Publishers::
fluid /ˈfluːɪd/ n - a substance, such as a liquid or gas, that can flow, has no fixed shape, and offers little resistance to an external stress
adj - capable of flowing and easily changing shape
- of, concerned with, or using a fluid or fluids
- constantly changing or apt to change
- smooth in shape or movement; flowing
Etymology: 15th Century: from Latin fluidus, from fluere to flowˈfluidness n
'body fluid' also found in these entries (note: many are not synonyms or translations):