antithrombin

adj. against thrombin (Medicine)

Antithrombin is a small protein molecule that inactivates several enzymes of the coagulation system. It is a glycoprotein produced by the liver and consists of 432 amino acids. It contains three disulfide bonds and a total of four possible glycosylation sites. α-antithrombin is the dominant form of antithrombin found in blood plasma and has an oligosaccharide occupying each of its four glycosylation sites. A single glycosylation site remains consistently un-occupied in the minor form of antithrombin, β-antithrombin.
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Antithrombin /an·ti·throm·bin/ any naturally occurring or therapeutically administered substance that neutralizes the action of thrombin and thus [more]Antithrombin - Community and Resources

n. antithrombin, against thrombin (Medicine)

noun
substance present in the blood which prevents clotting