noun, plural se·rums, se·ra [seer–uh] /ˈsɪər ə/.
- the clear, pale-yellow liquid that separates from the clot in the coagulation of blood; blood serum.
- immune serum.
- any watery animal fluid.
- the thin, clear part of the fluid of plants.
- milk whey.
noun plural -rums or -ra (-rə)
- See blood serum
- antitoxin obtained from the blood serum of immunized animals
- physiol zoology clear watery fluid, esp that exuded by serous membranes
- a less common word for whey
n.1670s, “watery animal fluid,” from Latin serum “watery fluid, whey,” from PIE root *ser- (2) “to run, flow” (cf. Greek oros “whey;” Sanskrit sarah “flowing,” sarit “brook, river”). First applied 1893 to blood serum used in medical treatments. adj.
- Relating to or derived from serum.
n. pl. se•rums
- A watery fluid, especially one that moistens the surface of serous membranes or that is exuded by such membranes when they become inflamed.
- The clear yellowish fluid obtained upon separating whole blood into its solid and liquid components.
- Such fluid from the tissues of immunized animals, containing antibodies and used to transfer immunity to another individual.
Plural serums sera
- See blood serum.
- Blood serum extracted from an animal that has immunity to a particular disease. The serum contains antibodies to one or more specific disease antigens, and when injected into humans or other animals, it can transfer immunity to those diseases.