Origin of prothrombin
International Scientific Vocabulary
First Known Use: 1898
Medical Definition of prothrombin
: a plasma protein produced in the liver in the presence of vitamin K and converted into thrombin by the action of various activators (as thromboplastin) in the clotting of blood
Seen and Heard
What made you want to look up prothrombin? Please tell us where you read or heard it (including the quote, if possible).