[noun], [adjective] - (a substance) which flows and is not solidWhen you have a fever it's best to drink plenty of fluid(s) (= have a lot to drink). [C or U]The doctor drained (off)/removed some fluid (= unwanted liquid) from her lung. [U]A loss of bodily fluids, for example by getting too hot and not drinking enough, can lead to dehydration and death. [C](specialized) In chemistry, a fluid is a substance which flows and fills the container it is in, so liquids and gases are both called fluids.(figurative) The dancer's movements were beautifully fluid (= smooth and flowing).(figurative) If situations/ideas/plans are fluid, they are not fixed and are likely to change.The military situation is still fluid.(dated) A fluid ounce is a measurement of liquid equal to (UK) 0.024 or (US) 0.030 of a litre.There are 20 fluid ounces in a British pint and 16 in an American one.
FLUID
Meaning of FLUID in English
Cambridge English vocab. Кембриджский английский словарь. 2012