One of the four phases of matter, a liquid is a fluid whose volume is fixed under conditions of constant temperature and pressure; and, whose shape is usually determined by the container it fills. Liquids tend to pull themselves together into droplets due to surface tension. The kinetic energy in a liquid is greater than that of a solid, but less than that of a gas. A liquids atoms/molecules are "slippery"; that is, they slide over one another, allowing the liquid to flow.
It should be noted that glass at normal temperatures is not a "supercooled liquid", but a solid. See the article on glass for more details.
See also gas, solid, plasma, ripple.
In linguistics, "liquid" can also refer to a liquid consonant.
