ti·​ter | \ ˈtī-tər How to pronounce titer (audio) \
variants: or chiefly British
plural titers

Definition of titer

1 : the strength of a solution or the concentration of a substance in solution as determined by titration … if the analyst is using an oxalic acid solution to titrate a solution of calcium oxide, the titer of the oxalic acid solution would be expressed as its CaO titer, or the weight of CaO that is consumed by 1mL of the oxalic acid solution.— John Kenkel
2 : a measure of the concentration of a substance (such as an antibody) in a blood sample that is obtained by subjecting the sample to serial dilutions (as with saline) to determine the maximum dilution at which the sample retains a specific activity (such as neutralizing an antigen) and that is often expressed as a ratio (such as 1:200) I have examples of people who clearly were infected who are antibody negative. They probably have such a low titer of antibody that it's below the level of the cutoff.— Anthony Fauci The Blood Center will also ensure that the plasma has high titers of antibodies against the coronavirus.— John Timmer also : a test for obtaining a blood titer often used before another noun an antibody titer test

Examples of titer in a Sentence

Recent Examples on the Web Two to four weeks after vaccination, the researchers found the median live-neutralizing antibody titer for the Pfizer and Moderna vaccines to be about 1,790 and 5,850, respectively. BostonGlobe.com, 15 Oct. 2021 Whereas when people who are getting infected, who were without symptoms, who are not vaccinated, generally the titer or the level of virus, relatively speaking, is higher than in the vaccinated individuals. CBS News, 16 May 2021 In the next few months, scientists will get a better sense of how to use antibody titer data, and many are already looking at additional boosters for the vaccine. Chronicle Advice Team, San Francisco Chronicle, 12 Apr. 2021 Creating a higher titer, or antibody level, is like flooding a battlefield with soldiers in the face of a fierce enemy. Matthew Herper, STAT, 27 Feb. 2021 In the study, participants had neutralizing antibodies, measured in a unit called a geometric mean titer, of 224 to 354, on day 29 after their first vaccine dose; those levels reached 288 to 488 by day 57. Matthew Herper, STAT, 13 Jan. 2021 The American Red Cross is working on strategies for identifying and recruiting high-titer donors. Amy Dockser Marcus, WSJ, 27 Sep. 2020 The findings suggest deaths were 35% lower in the high-titer group. Author: Jonathan Lamire And Mike Stobbe, Anchorage Daily News, 24 Aug. 2020 The emergency-use authorization covers both high- and low-titer plasma. Amy Dockser Marcus, WSJ, 27 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'titer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of titer

1861, in the meaning defined at sense 1

History and Etymology for titer

French titre title, proportion of gold or silver in a coin, from Old French title inscription, title

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Last Updated

26 Oct 2021

Cite this Entry

“Titer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/titer. Accessed 26 Oct. 2021.

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More Definitions for titer


ti·​ter | \ ˈtīt-ər How to pronounce titer (audio) \
variants: or chiefly British titre \ ˈtī-​tər also ˈtē-​ \

Medical Definition of titer

1a : the strength of a solution or the concentration of a substance in solution as determined by titration
b : the dilution of a serum containing a specific antibody at which the solution just retains a specific activity (as neutralizing or precipitating an antigen) which it loses at any greater dilution a test for toxoplasmosis antibodies yielded a titer of 1:1024
2 : the solidifying point of the fatty acids liberated from a fat that is determined by melting the acids in a tube and noting the temperature at which they solidify again on cooling

Other Words from titer

titered \ -​ərd How to pronounce titer (audio) \ adjective


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