1. The colorless watery fluid of the blood and lymph that contains no cells, but in which the blood cells (erythrocytes, leukocytes, and thrombocytes) are suspended Noun
2. A green slightly translucent variety of chalcedony used as a gemstone Noun
3. (physical chemistry) a fourth state of matter distinct from solid or liquid or gas and present in stars and fusion reactors; a gas becomes a plasma when it is heated until the atoms lose all their electrons, leaving a highly electrified collection of nuclei and free electrons Noun