titer

noun

ti·​ter ˈtī-tər 

variants or chiefly British titre

plural titers

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

Example Sentences

Recent Examples on the Web

Only high-antibody-titer convalescent plasma was authorized for use. —Verywell Health, 27 Jan. 2023

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

See More

Word History

Etymology

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

First Known Use

1861, in the meaning defined at sense 1

Medical Definition

titer

noun

ti·​ter ˈtīt-ər 

variants or chiefly British titre

ˈtī-tər also ˈtē-

1

a

: the strength of a solution or the concentration of a substance in solution as determined by titration

b

: 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

a test for toxoplasmosis antibodies yielded a titer of 1:1024

Children with rash had higher antibody titers than those without rash …

—Anne A. Gershon et al., The Journal of the American Medical Association

also : a test for obtaining a blood titer

—often used before another noun

an antibody titer test

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

titered

-ərd 

adjective