1》 a circumstance, fact, or influence that contributes to a result.
↘ Biology a gene that determines a hereditary characteristic.
2》 Mathematics a number or quantity that when multiplied with another produces a given number or expression.
↘a number or algebraic expression by which another is exactly divisible.
3》 Physiology any of a number of substances in the blood which are involved in coagulation.
4》 a business agent.
↘a company that buys a manufacturer's invoices at a discount and takes responsibility for collecting the payments due on them.
↘ Scottish a land agent or steward.
1》 ( ~ something in/out ) include (or exclude) something as a relevant element when making a decision.
2》 Mathematics another term for ~ize .
3》 sell (one's receivable debts) to a ~.
ME (meaning 'doer', also in the Scots sense 'agent'): from Fr. facteur or L. ~ , from fact- , facere 'do'.