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mono·​clo·​nal ˌmä-nə-ˈklō-nᵊl How to pronounce monoclonal (audio)
: produced by, being, composed of, or caused by cells derived from a single cell
… Dr. [Lawrence] Kaplan said tumors that were monoclonal, arising from a single malignant cell, indicated poor survival.Marilyn Chase
especially : relating to, being, or caused by a monoclonal antibody or monoclonal antibodies
monoclonal assays
see also monoclonal gammopathy


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plural monoclonals
: monoclonal antibody
But now researchers say that new ways of modifying antibodies promise to deliver monoclonals in more effective forms, with fewer side effects and at lower cost.Lawrence M. Fisher

Examples of monoclonal in a Sentence

Recent Examples on the Web
As with many monoclonal antibodies, CAB-I47 makes contact with the receptor-binding domain to block binding to the human ACE2 receptor. William A. Haseltine, Forbes, 10 Feb. 2023 Evusheld is a combination of two monoclonal antibodies: tixagevimab and cilgavimab. Carla Delgado, Verywell Health, 8 Feb. 2023 Antibody drugs—also known as monoclonal antibodies—have been an important weapon against the virus. Emily Mullin, WIRED, 8 Feb. 2023 Attacking amyloid with monoclonal antibodies is not without risks. Sue Halpern, The New Yorker, 7 Feb. 2023 As with the once-effective monoclonal antibodies, CCP given to high-risk Covid-19-positive outpatients dramatically reduces the risk of hospitalization. Nigel Paneth, STAT, 6 Feb. 2023 Unfortunately, monoclonal antibodies, which had been useful earlier in the pandemic, are no longer effective against the currently circulating variants and have been removed from the market. Karen Weintraub, USA TODAY, 5 Feb. 2023 Brii Biosciences has developed a combination of monoclonal antibodies, BRII-196 and BRII-198. Verywell Health, 27 Jan. 2023 Evusheld is the commercial name of an AstraZeneca drug that combines two monoclonal antibodies, tixagevimab and cilgavimab. Melissa Healystaff Writer, Los Angeles Times, 27 Jan. 2023
Pfizer plans to charge $295 for its shot, and Sanofi sells the monoclonal immunization for $495. Kyle Orland, Ars Technica, 22 Sep. 2023 Newsletters Sign up for Daily Recap A roundup of our top stories of the day in health and medicine The CDC’s statement said availability of the monoclonal product, whose scientific name is nirsevimab, is also playing into the current shortage. Helen Branswell, STAT, 24 Oct. 2023 But monoclonal treatments are also pricey, and different combinations of antibodies would still be required for each snake species. Cassandra Willyard, Scientific American, 19 Sep. 2023 Someone had to be inside the White House making sure that resources were made appropriately to expand testing, to expand monoclonal and develop vaccines, and that was part of my role. ABC News, 29 Aug. 2023 The monoclonal version with just one strain outperformed each of the bivalent options. Claire Bugos, Verywell Health, 16 June 2023 This monoclonal could be a notable measure of protection for babies, wherever it's approved, available and accessible to those who need it. Sasha Pezenik, ABC News, 4 Nov. 2022 Unable to get enough from the feds for his state, Florida Gov. Ron DeSantis in September went around the Administration to purchase the monoclonal from GSK and Vir. The Editorial Board, WSJ, 12 Jan. 2022 Regeneron started with its two-drug cocktail, REGEN-COV, and Lilly now has added a second monoclonal to its original drug, bamlanivimab, to provide more protection against COVID-19 variants. USA Today, 17 Apr. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'monoclonal.' 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


1914, in the meaning defined above


1980, in the meaning defined above

Time Traveler
The first known use of monoclonal was in 1914

Dictionary Entries Near monoclonal

Cite this Entry

“Monoclonal.” Dictionary, Merriam-Webster, Accessed 21 Apr. 2024.

Medical Definition


1 of 2 adjective
mono·​clo·​nal ˌmän-ə-ˈklōn-ᵊl How to pronounce monoclonal (audio)
: produced by, being, or composed of cells derived from a single cell
a monoclonal tumor
especially : relating to or being an antibody derived from a single cell in large quantities for use against a specific antigen (as a cancer cell)


2 of 2 noun
: a monoclonal antibody
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