Definition of factor in English:

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Pronunciation: /ˈfaktə/


1A circumstance, fact, or influence that contributes to a result: his skill was a factor in ensuring that so much was achieved she worked fast, conscious of the time factor
More example sentences
  • Similarly, family and friends of students have been considered an influential factor in choosing an agriculture major.
  • Timely administration is a key factor in achieving positive results with hyaluronidase.
  • What is the greatest factor in contributing to childhood obesity?
element, part, component, ingredient, strand, constituent, point, detail, item, feature, facet, aspect, characteristic, consideration, influence, circumstance, thing, determinant
1.1 Biology A gene that determines a hereditary characteristic: the Rhesus factor
More example sentences
  • Homeobox genes encode transcription factors involved in many aspects of developmental processes.
  • These findings provide insights into how genomes and environmental factors interact to determine phenotypes.
  • In related studies, the genetic factors determining the conformation of curd was analyzed.
2A number or quantity that when multiplied with another produces a given number or expression: an amount that exceeds it by a factor of 1000 or more
More example sentences
  • Multiply your X factor by 159 to reach a daily total of 2,067 calories a day.
  • Here, the change often seemed to be proportional to the molecular weight of the solute multiplied by a factor of two, three or four.
  • Take the maximum draw weight of the bow required and multiply this by a factor of 5.
2.1 Mathematics A number or algebraic expression by which another is exactly divisible.
Example sentences
  • So what about those Fibonacci numbers with no factors (apart from 1 and itself, of course)?
  • The fraction 10/12 can be reduced, because both the numerator and denominator have factors of 2.
  • A number that only has two factors, one and itself, is called a prime number.
3A level on a scale of measurement.
Example sentences
  • You can select from the standard list of scale factors or key in your own.
  • Your weirdness factor goes off the scale of this test.
  • As expected, the sympathy factor has tilted the scales of a nation already dissatisfied with the government.
3.1(With numeral) a sunscreen of the sun protection factor specified: factor 30 sun cream
More example sentences
  • The application of sunscreen with an SPF factor of 8 reduces production of vitamin D by 95%.
  • For tropical sun exposure, a protection factor of 15 or higher should be more than adequate for all day exposure.
4 Physiology Any of a number of substances in the blood, mostly identified by numerals, which are involved in coagulation. See factor VIII.
Example sentences
  • These include a change in the balance between procoagulant and anticoagulant factors in the blood.
  • In hemostasis, there is a balance between procoagulant factors and natural anticoagulant proteins.
  • In recent years literature is emerging on the role of different factors of blood coagulation in arterial thrombosis.
5An agent who buys and sells goods on commission: his father was chief factor for the Hudson’s Bay Company
More example sentences
  • The brassfounders' traditional use of factors and agents accounts for the maddening anonymity of the catalogues.
  • Each district was normally headed by a chief factor, who reported to the departmental governor.
agent, representative, deputy, middleman, intermediary, go-between;
estate manager, land agent, land steward, reeve
5.1A company that buys a manufacturer’s invoices at a discount and takes responsibility for collecting the payments due on them.
Example sentences
  • Usually notice is given to the account debtor and the debts are collected directly by the factor.
  • It is the factor who then receives payment from the importer.
5.2Scottish A land agent or steward: the house became home to the estate factor
More example sentences
  • The factor who manages the estate is Peter Graham from Bidwells in Inverness.
  • Within two years they were selling paintings and objets d' art, and within five years they had moved into the estate factor's house and mothballed Whittingehame.
  • Peter Ord, the factor of Balmoral Estate, said he hoped that work would start on the scheme within the next 12 months.


[with object]
1 Mathematics another term for factorize. last year researchers factored a number 155 digits long
More example sentences
  • It meant that the resources needed to use previously known algorithms for factoring numbers of a given size could now be used to factor significantly larger numbers.
  • I don't understand how to start out factoring this algebra.
  • But if you could factor large numbers then you could break these codes.
2(Of a company) sell (its invoices) to a factor: they collected rents while he factored these forfeited estates
More example sentences
  • Of considerably more importance is that Scanchem is now factoring its invoices, and thus increasing its apparent borrowing, the outstanding amounts being secured by a charge on the book debts of the company, as is normal.
  • They were however concerned that they might be factoring bogus invoices.
  • Consider factoring or invoice discounting - drawing down bank finance against your debtor balance.

Phrasal verbs

factor something in (or out)

Include (or exclude) something as a relevant element when making a decision: when the psychological costs are factored in, a different picture will emerge
More example sentences
  • The Department of Education had estimated the bill for compensation would reach €508m, rising to €610m when legal and administration costs were factored in.
  • Courts Service chief executive officer PJ Fitzpatrick said they did not see the original lease until much later and were unaware refurbishment costs were factored in to the rental price.
  • Puppeteers argue their fees are low if their working hours are factored in, including preparation for the show and the cleanup.



Example sentences
  • It should be noted that the number of tickets in each column and row is six, a factorable number divisible by two and three as well as by six and one.


Late Middle English (meaning 'doer', also in the Scots sense 'agent'): from French facteur or Latin factor, from fact- 'done', from the verb facere.

Words that rhyme with factor

abstractor, actor, attractor, compactor, contractor, enactor, exactor, extractor, infractor, protractor, redactor, refractor, tractor, transactor

For editors and proofreaders

Line breaks: fac¦tor

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