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
John Kenkel2
: 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
Anthony FauciThe Blood Center will also ensure that the plasma has high titers of antibodies against the coronavirus.—John Timmer
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
Lab testing determined Misty had a low titer on Valley Fever blood work.
—The Arizona Republic, 26 Jan. 2024
At this time, the low titer is suspected to be related to previous exposure rather than an active infection but should be kept an eye on with her future vet.
—The Arizona Republic, 26 Jan. 2024
Mice that received the antibodies displayed significantly lower weight loss, more normal pulmonary function, and fewer viral titers in lung tissue than in the control group.
—William A. Haseltine, Forbes, 17 Mar. 2023
The implication is that if the vaccine elicits a similar or higher antibody titer, and if people who’ve recovered from Covid-19 are immune from catching the disease again for some period of time, then the vaccine should also provide temporary immunity.
—Jeremy Kahn, Fortune, 24 Aug. 2020
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The Arizona Republic, 26 Jan. 2024
At this time, the low titer is suspected to be related to previous exposure rather than an active infection but should be kept an eye on with her future vet.
—The Arizona Republic, 26 Jan. 2024
Mice that received the antibodies displayed significantly lower weight loss, more normal pulmonary function, and fewer viral titers in lung tissue than in the control group.
—William A. Haseltine, Forbes, 17 Mar. 2023
The implication is that if the vaccine elicits a similar or higher antibody titer, and if people who’ve recovered from Covid-19 are immune from catching the disease again for some period of time, then the vaccine should also provide temporary immunity.
—Jeremy Kahn, Fortune, 24 Aug. 2020
See all Example Sentences for titer
Articles Related to titer
Dictionary Entries Near titer
Cite this Entry
“Titer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/titer. Accessed 1 Dec. 2024.
Copy CitationMedical 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
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
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