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

(not comparable) Of or relating to fluid. / In a state of flux; subject to change. / Moving smoothly, or giving the impression of a liquid in motion. / (of an asset) Convertible into cash.

The quality of being fluid.

plural of fluid

(humorous) A mythical automotive material used either in jokes or to gauge how inept someone is in basic auto mechanics.

fuel in fluid form used in a cigarette lighter

A white, opaque fluid, applied to paper to mask textual errors; used especially to mask errors in typing so that corrections may be overtyped.

The mixture of blood and cellular debris from the uterus that constitutes the menses

(Australia, slang) Beer.

A British unit of volume equal to 60 minims or 3.55 ml.