The colorless fluid part of blood, lymph, or milk, in which corpuscles or fat globules are suspended. An ionized gas consisting of positive ions and free electrons in proportions resulting in more or less no overall electric charge, typically at low pressures (as in the upper atmosphere and in fluorescent lamps) or at very high temperatures (as in stars and nuclear fusion reactors). A dark green, translucent variety of quartz used in mosaic and for other decorative purposes.