IgA

noun

ˌī-(ˌ)jē-ˈā How to pronounce IgA (audio)
1
: a class of immunoglobulins including antibodies found in external bodily secretions (such as saliva, tears, and sweat)
2
: an antibody of the class IgA

Examples of IgA in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In the blood, two types of antibodies (IgA and IgG) increased by several fold after vaccination compared with the placebo group. — Ars Technica, 6 Mar. 2025 Living With IgA Nephropathy In terms of overall prognosis, individual cases of IgA nephropathy vary. — Mark Gurarie, Health, 30 Sep. 2024

Word History

Etymology

immunoglobulin

First Known Use

1969, in the meaning defined at sense 1

Time Traveler
The first known use of IgA was in 1969

Browse Nearby Words

IG
IgA
Igala
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Cite this Entry

“IgA.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/IgA. Accessed 21 Apr. 2025.

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Medical Definition

IgA

noun
ˌī-ˌjē-ˈā How to pronounce IgA (audio)
1
: a class of immunoglobulins that include antibodies found in external bodily secretions (as saliva, tears, and sweat)
2
: an immunoglobulin of the class IgA

More from Merriam-Webster on IgA

Britannica.com: Encyclopedia article about IgA

Last Updated: - Updated example sentences
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