factor IX

noun
\ -ˈnīn How to pronounce factor IX (audio) \

Definition of factor IX

: a clotting factor that activates factor VIII and whose deficiency is associated with hemophilia

called also Christmas factor

First Known Use of factor IX

1955, in the meaning defined above

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The first known use of factor IX was in 1955

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Cite this Entry

“Factor IX.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/factor%20IX. Accessed 10 Jul. 2020.

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factor IX

noun
\ -ˈnīn How to pronounce factor IX (audio) \

Medical Definition of factor IX

: a clotting factor that activates factor VIII and whose absence is associated with hemophilia B

called also autoprothrombin II, Christmas factor

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