titer

American  

[tahy-ter, tee-] / ˈtaɪ tər, ˈti- /

especially British, titre

noun

Chemistry, Medicine/Medical.

1. the strength of a solution as determined by titration with a standard substance.

2. the concentration of a substance in a given sample as determined by titration.

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titer British  

/ ˈtiː-, ˈtaɪtə /

noun

1. the usual US spelling of titre

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titer Scientific  

/ tī′tər /

1. The concentration of a substance in solution or the strength of such a substance as determined by titration.

2. The minimum volume of a solution needed to cause a particular result in titration.

3. The concentration of antibodies present in the highest dilution of a serum sample at which visible clumps with an appropriate antigen are formed.

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Etymology

Origin of titer

1830–40; < French titre title, qualification, fineness of alloyed gold or silver < Latin titulus title

Example Sentences

You might have heard about a titer test, which looks at the amount of antibodies in a person’s blood in order to confirm that they are immune.

From Slate • Mar. 12, 2025

A: In our model, we give it at a very low titer and it causes a very significant, very itchy, full body rash.

From Science Magazine • Oct. 26, 2023

“Omicron BA.2 is not neutralized with detectable titer by any of the therapeutic monoclonal antibodies, including sotrovimab,” researchers from the NYU Grossman School of Medicine said in the study, which hasn’t been peer-reviewed.

From Washington Times • Feb. 21, 2022

The antibody titer, or "score" — an example of which is pictured above — refers to the total number of COVID-19 antibodies found in a person's blood.

From Salon • Aug. 13, 2021

They are then heated to 130° C. as rapidly as possible with stirring, and transferred, after they have cooled somewhat, to the usual 1-in. by 4-in. titer tube.

From Soap-Making Manual A Practical Handbook on the Raw Materials, Their Manipulation, Analysis and Control in the Modern Soap Plant. by Thomssen, E. G.