fluid

adj. of a substance that can easily change its shape; flexible, changeable; smooth, graceful; easily converted into cash

n. substance whose molecules move freely and that tends to take the shape of its container (i.e. liquid or gas)

FLUID (Fast Light User Interface Designer) is a graphical editor that is used to produce FLTK source code. FLUID edits and saves its state in text .fl files, which can be edited in a text editor for finer control over display and behavior.After designing the application, FLUID compiles the .fl file into a .cxx file, which defines all the objects from the .fl file, and an .h file, which declares all the global ones. FLUID also supports localization of label strings using message files and the GNU gettext or POSIX catgets interfaces.A simple program can be made by putting all non-interface code (including a main function) into the .fl file, thus making the .cxx file a single source file to compile. Most programs are more complex than this, so other .cxx files can be written that call the FLUID functions. These .cxx files must #include the .h file, or they can #include the .cxx file so it still appears to be a single source file.
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A fluid is defined as a substance that continually deforms (flows) under an applied shear stress regardless of the magnitude of the applied stress. It is a subset of the phases of matter and includes liquids, gases, plasmas and, to some extent, plastic solids.Fluids are also divided into liquids and air. Liquids form a free surface (that is, a surface not created by their container) while gases do not. The distinction between solids and fluids is not so obvious. The distinction is made by evaluating the viscosity of the matter: for example Silly Putty can be considered either a solid or a fluid, depending on the time period over which it is observed.
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Noun
1. a substance that is fluid at room temperature and pressure
(hypernym) substance, matter
(hyponym) coolant
2. a continuous amorphous substance that tends to flow and to conform to the outline of its container: a liquid or a gas
(hypernym) substance, matter
(hyponym) gas
Adjective
1. subject to change; variable; "a fluid situation fraught with uncertainty"; "everything was unstable following the coup"
(synonym) unstable
(similar) changeable, changeful
2. characteristic of a fluid; capable of flowing and easily changing shape
(synonym) runny
(similar) liquid
3. smooth and unconstrained in movement; "a long, smooth stride"; "the fluid motion of a cat"; "the liquid grace of a ballerina"; "liquid prose"
(synonym) flowing, fluent, liquid, smooth
(similar) graceful
4. in cash or easily convertible to cash; "liquid (or fluid) assets"
(synonym) liquid
(similar) disposable
5. affording change (especially in social status); "Britain is not a truly fluid society"; "upwardly mobile"
(synonym) mobile
(similar) changeable, changeful

v. flow, outflow; stream; drift

Liquid.