antibody
Americannoun
PLURAL
antibodies-
any of numerous Y -shaped protein molecules produced by B cells as a primary immune defense, each molecule and its clones having a unique binding site that can combine with the complementary site of a foreign antigen, as on a virus or bacterium, thereby disabling the antigen and signaling other immune defenses. Ab
-
antibodies of a particular type collectively.
noun
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012-
Any of numerous proteins produced by B lymphocytes in response to the presence of specific foreign antigens, including microorganisms and toxins. Antibodies consist of two pairs of polypeptide chains, called heavy chains and light chains, that are arranged in a Y-shape. The two tips of the Y are the regions that bind to antigens and deactivate them.
-
Also called immunoglobulin
Closer Look
Like other vertebrates, humans possess an effective immune system that uses antibodies to fight bacteria, viruses, and cancer cells. Antibodies are complex, Y-shaped protein molecules. The immune system's B lymphocytes, which are produced by the bone marrow, develop into plasma cells that can generate a huge variety of antibodies, each one capable of combining with and destroying an antigen, a foreign molecule. Antibodies react to very specific characteristics of different antigens, binding them to the top ends of their Y formation. Once the antibody and antigen combine, the antibodies deactivate the antigen or lead it to macrophages(a kind of white blood cell) that ingest and destroy it. High numbers of a particular antibody may persist for months after an invasion, eventually diminishing. However, the B cells can quickly manufacture more of the same antibody if exposure to the antigen recurs. Vaccines work by “training” B cells to recognize and react quickly to potential disease molecules.
Etymology
Origin of antibody
Compare meaning
How does antibody compare to similar and commonly confused words? Explore the most common comparisons:
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Maternal vaccination during the third trimester of pregnancy and passive immunization of newborns using long-acting antibodies are being rolled out in many countries.
From Science Daily
"The bumpier, irregular surface of the virulent strains exposes parts of the virus that are normally hidden, allowing certain antibodies to attach more easily," Dr. Bibby said.
From Science Daily
They then used a gentle pre-transplant preparation involving immune-targeting antibodies and low-dose radiation, followed by a transplant of blood stem cells and islet cells from an unrelated donor, to restore blood sugar control.
From Science Daily
Valneva said that antibody levels remained well above baseline across all six Lyme disease serotypes and all age groups in the trial.
He notes that common tools such as antibodies and nanobodies often bind too tightly to DNA, which can interfere with the cell's own repair systems.
From Science Daily
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.