Serum

noun, plural serums, sera
[seer-uh] /ˈsɪər ə/ (Show IPA)
1.
the clear, pale-yellow liquid that separates from the clot in the coagulation of blood; blood serum.
2.
immune serum.
3.
any watery animal fluid.
4.
the thin, clear part of the fluid of plants.
5.
milk whey.
noun (pl) -rums, -ra (-rə)
1.
See blood serum
2.
antitoxin obtained from the blood serum of immunized animals
3.
(physiol, zoology) clear watery fluid, esp that exuded by serous membranes
4.
a less common word for whey

serum se·rum (sēr’əm)
n. pl. se·rums or se·ra (sēr’ə)

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.

serum
(sîr’əm)
Plural serums or 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.