thrombin

American  

[throm-bin] / ˈθrɒm bɪn /

noun

Biochemistry.

1. an enzyme of the blood plasma that catalyzes the conversion of fibrinogen to fibrin, the last step of the blood clotting process.

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thrombin British  

/ ˈθrɒmbɪn /

noun

1. biochem an enzyme that acts on fibrinogen in blood causing it to clot

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thrombin Scientific  

/ thrŏm′bĭn /

1. An enzyme in blood that catalyzes the conversion of fibrinogen to fibrin and is essential to the coagulation of blood.

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Etymology

Origin of thrombin

First recorded in 1895–1900; thromb(us) + -in ²

Example Sentences

When exposed to thrombin, a substance that promotes clotting, the cells had a reduced ability to produce t-PA, a natural compound that helps break down clots.

From Science Daily • Mar. 28, 2026

We found that the enzyme’s snipping of these threads that stitch myelin to the axon can be controlled by the perinodal astrocyte’s release of an inhibitor of thrombin.

From Scientific American • Mar. 12, 2020

By silencing a gene for antithrombin, fitusiran enables a rise in the production of the enzyme thrombin, which helps the blood to clot.

From Nature • Oct. 15, 2019

It works by blocking thrombin, a blood enzyme involved with clotting.

From Reuters • Nov. 18, 2013

The last step in the change is the action of thrombin upon fibrinogen to form fibrin, and the clot is complete.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 1 "Bisharin" to "Bohea" by Various