1
: a class of immunoglobulins including the most common antibodies circulating in the blood that facilitate the phagocytic destruction of microorganisms foreign to the body, that bind to and activate complement, and that are the only immunoglobulins to cross over the placenta from mother to fetus
2
: an antibody of the class IgG

Examples of IgG in a Sentence

Recent Examples on the Web Some allergy tests look for another protein, immunoglobulin G (IgG). Rachel Murphy, Verywell Health, 26 May 2023 That IgG can move from the blood across the mucosa. Steven Strogatz, Quanta Magazine, 5 Apr. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'IgG.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1965, in the meaning defined at sense 1

Time Traveler
The first known use of IgG was in 1965

Dictionary Entries Near IgG

Cite this Entry

“IgG.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/IgG. Accessed 27 Feb. 2024.

Medical Definition

1
: a class of immunoglobulins that include the most common antibodies circulating in the blood, that facilitate the phagocytic destruction of microorganisms foreign to the body, that bind to and activate complement, and that are the only immunoglobulins to cross over the placenta from mother to fetus
2
: an immunoglobulin of the class IgG

More from Merriam-Webster on IgG

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