factor X

noun
\ -ˈten How to pronounce factor X (audio) \

Definition of factor X

: a clotting factor that is produced primarily in the liver under the influence of vitamin K and in its activated form is a proteolytic enzyme that converts prothrombin to thrombin in a reaction dependent on calcium ions and phospholipids and accelerated by factor V

Examples of factor X in a Sentence

Recent Examples on the Web In Strategy 1, the revealing factor X is 3160/1600 = 1:98. Nicholas Diaco, Scientific American, "Privacy and Counterfeit Coins," 20 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'factor X.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of factor X

1954, in the meaning defined above

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The first known use of factor X was in 1954

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Cite this Entry

“Factor X.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/factor%20X. Accessed 3 Aug. 2020.

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More Definitions for factor X

factor X

noun
\ -ˈten How to pronounce factor X (audio) \

Medical Definition of factor X

: a clotting factor that is produced primarily in the liver under the influence of vitamin K and in its activated form is a proteolytic enzyme that converts prothrombin to thrombin in a reaction dependent on calcium ions and phospholipids and accelerated by factor V

called also Stuart-Prower factor

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