A fluid is a substance that can move easily and change shape such as water (liquids), or air (gases), or plasmas. They can 'flow'- flow and fluids both come from the same English word roots (Latin: fluere "to flow") and are pronounced similarly. The physics of fluids is called fluid mechanics.
Fluids usually take on the shape of their containers, in contrast to solids which maintain their own shape.
Some things are not exactly fluid and not exactly solid, such as Silly Putty. Powders are made up of small solids that appear to flow but don't actually.
Most fluids have a freezing point. At this temperature it becomes solid.
Wikiwand in your browser!
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.
