Wiktionary
hirudin
n. (context medicine English) A peptide, obtained from the salivary glands of leeches, that is used as an anticoagulant
Wikipedia
Hirudin
Hirudin is a naturally occurring peptide in the salivary glands of medicinal leeches (such as Hirudo medicinalis) that has a blood anticoagulant property. This is fundamental for the leeches’ alimentary habit of hematophagy, since it keeps the blood flowing after the initial phlebotomy performed by the worm on the host’s skin.
Usage examples of "hirudin".
Nowadays, doctors can treat conditions like haemophilia with clotting factors like thrombin and protein C, and conditions of the opposite kind with warfarin and hirudin, but Sheena's condition wasn't amenable to any kind of continuous therapy.