immunoglobulin

IPA/ˌɪm.jəːn.əʊˈɡlɒb.jə.lɪn/
IPA/ˌɪm.jə.noʊˈɡlɑː.bjə.lɪn/

immunoglobulin — noun

  • immunoglobulinsingular
  • immunoglobulinsplural

1. a type of protein made by the immune system that helps the body recognise and at

1.nounC1
Definition

a type of protein made by the immune system that helps the body recognise and attack viruses, bacteria, and other harmful foreign substances by acting as an antibody

Example

Dr. Okafor tested Wen's immunoglobulin levels after the patient had three infections in two months.

collocation: immunoglobulin level(s)

Nadia's research team is studying how immunoglobulin binds to the outer surface of the flu virus.

how immunoglobulin binds to [pathogen]

Common collocations
  • immunoglobulin level(s)
  • immunoglobulin count
  • immunoglobulin injection
  • immunoglobulin therapy
  • immunoglobulin deficiency
  • intravenous immunoglobulin (IVIG)
Synonyms
  • antibody

    Almost interchangeable in everyday speech; 'antibody' emphasises the immune function, while 'immunoglobulin' refers to the protein structure itself. In strict usage, all antibodies are immunoglobulins, but some immunoglobulins (e.g. surface Ig on B cells) have roles beyond free-floating antibody activity.

Grammar Patterns

immunoglobulin + verb (is/produces/fights)

adjective + immunoglobulin (high/low/normal)

Usage Note

In medical writing the term is often shortened to Ig (capital I, lowercase g). There are five main classes: IgA, IgD, IgE, IgG, and IgM — each has a different job in the immune system. Both immunoglobulin and Ig have plural forms: immunoglobulins and Igs (e.g. 'the five Igs' or 'elevated Igs').

Common Mistakes

My antibody count is low.
My immunoglobulin level is low.
In clinical lab reports, 'immunoglobulin' is the standard measurement term; 'antibody' describes the biological function, not the lab value.

Word family

Synonym discussion

Sense: noun/1

All three words relate to blood proteins, but their scope differs. Antibody is the broadest functional term — any protein that recognises a specific antigen counts as an antibody. Immunoglobulin is the biochemical name for that same class of proteins and is the preferred term in lab reports and clinical studies (e.g. 'immunoglobulin levels'). Globulin refers to any of a large family of simple proteins in blood serum; immunoglobulins are just one subset of globulins. Gamma globulin is an older clinical term for the fraction of blood plasma that contains most immunoglobulins; it is still used when referring to injection-based treatments such as gamma globulin shots. In everyday hospital use, a doctor might say 'your immunoglobulins are low' but will order a 'gamma globulin infusion' — the two terms describe the same therapy from different historical angles.

antibody ↗globulingamma globulin

Common collocations

Nouns

Phrases

  • intravenous immunoglobulin (IVIG)
  • immunoglobulin G (IgG)
  • immunoglobulin A (IgA)
  • immunoglobulin M (IgM)

Etymology

LatinEnglish

Coined in the 1950s from immuno- (meaning 'related to the immune system', from Latin immunis 'exempt from public service') and globulin (a type of simple protein, from Latin globulus 'small sphere', referring to the spherical shape of the protein molecules).