factor IX

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

Definition of factor IX

 (Entry 1 of 3)

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

called also Christmas factor

Charles IX

biographical name (1)

Definition of Charles IX (Entry 2 of 3)

1550–1574 king of France (1560–74)

Frederick IX

biographical name (2)

Definition of Frederick IX (Entry 3 of 3)

1899–1972 king of Denmark (1947–72)

First Known Use of factor IX

Noun

1955, in the meaning defined above

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The first known use of factor IX was in 1955

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More Definitions for factor IX

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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