Definition of fibrin in English:



  • [mass noun] An insoluble protein formed from fibrinogen during the clotting of blood. It forms a fibrous mesh that impedes the flow of blood.

    • ‘It converts fibrinogen to fibrin, and unlike thrombin, is unaffected by heparin.’
    • ‘All of these agents convert plasminogen to plasmin, which in turn breaks down fibrin and promotes clot lysis.’
    • ‘Plasminogen binds to both fibrinogen and fibrin, thereby being incorporated into a clot as it is formed.’
    • ‘In the assay, the addition of thrombin to citrated plasma causes the conversion of fibrinogen to fibrin, yielding a stops bleeding much quicker.’
    • ‘Each microvillus contains a core of actin filaments organized in bundles by actin binding proteins such as villin, fibrin, and espin.’


Early 19th century: from fibre + -in.