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early 15c., "agent, deputy," from Middle French facteur "agent, representative," from Latin factor "doer or maker," agent noun from past participle stem of facere "to do" (see factitious). Sense of "circumstance producing a result" is from 1816.
1610s, "act as an agent," from factor (n.). The use in mathematics is attested from 1837. Related: Factored; factoring.
factor fac·tor (fāk'tər)
One that contributes in the cause of an action.
A mathematical component that by multiplication makes up a number or expression.
A substance, such as a vitamin, that functions in a specific biochemical reaction or bodily process, such as blood coagulation.
factor VIII n.
A factor in the clotting of blood, a deficiency of which is associated with hemophilia A. Also called antihemophilic factor, antihemophilic globulin, antihemophilic globulin A, proserum prothrombin conversion accelerator.
factor IX n.
A factor in the clotting of blood necessary for the formation of intrinsic blood thromboplastin; a deficiency of it causes hemophilia B. Also called antihemophilic globulin B, Christmas factor.
Verb To find the factors of a number or expression. For example, the number 12 can be factored into 2 and 6, or 3 and 4, or 1 and 12.