What does globulin mean?
Globulin is a technical name for a group of proteins, especially those found in blood plasma. The term belongs to the history of protein classification: globulins were traditionally distinguished by their solubility in water and dilute salt solutions, and serum protein electrophoresis separates them into fractions such as alpha, beta-, and gamma globulins. Gamma globulins include the immunoglobulins, the antibodies that recognize and help neutralize foreign substances. In medicine and laboratory science, "globulin" can therefore mean either a particular family of proteins or the measured globulin fraction in a blood sample. Outside these specialist contexts, the word is uncommon, but it connects a familiar laboratory measurement with the biological roles of immunity and transport. Its unusual name also preserves an older visual intuition: a globule is a small sphere, and globulin was named for the rounded appearance associated with this protein class.
nounGlobulin is any member of a diverse group of proteins, particularly abundant in blood plasma, that are generally soluble in water and dilute salt solutions. The term includes families such as alpha-, beta-, and gamma globulins, the latter including antibodies.
- A member of a group of proteins, especially those found in blood plasma, that are generally soluble in water and dilute salt solutions; the group includes alpha-, beta-, and gamma globulins, with the immunoglobulins belonging to the gamma-globulin fraction.
"The laboratory found that the patient's gamma globulin levels were unusually high."
"Serum protein electrophoresis separates albumin from the globulin fractions."
"Immunoglobulin G is one of the gamma globulins that circulate in blood and help neutralize pathogens."
Used when referring to several individual globulins or to globulins as a group; "globulin" remains singular in expressions such as "serum globulin" and "gamma globulin."
"Distinct globulins have specialized roles in blood plasma."
Its name points to a sphere, but its best-known globulins are microscopic defenders: antibodies.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does globulin come from?
The word was formed in English during the 19th century from the stem of "globule," ultimately Latin globulus, a diminutive of globus meaning "globe" or "ball," together with the chemical suffix -in. The glob- element reflected the traditional description of these proteins as rounded or globular. English words such as "globe," "globule," "globular," and "globose" preserve the same Latin root.
Related word forms
How globulin is actually used
Globulin is primarily a technical term used in biochemistry, medicine, and laboratory science. In medical usage, "gamma globulin" can refer to an electrophoretic protein fraction or, in historical clinical contexts, preparations containing antibodies.
Easily confused with globulin
Globulin is a broad group of proteins, whereas globin is the specific iron-containing protein that forms part of haemoglobin.
A globule is a small spherical body or drop, while globulin is a protein classified partly by its traditional globular form and solubility.