noun

1. 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 plasma.

2. A liquid (as opposed to a solid or gas).

3. (specifically, typically in the plural) Intravenous fluids.

adjective

1. Of or relating to fluid.

2. In a state of flux; subject to change.

3. Moving smoothly, or giving the impression of a liquid in motion.

Synonyms: fluent, fluxive, fluidical, liquid, unstable, variable