# factor

/ˈfæktɝ/ (US) · /fˈæktɐ/ (UK)

Source: https://englishreference.com/word/factor
Updated: 2026-08-15

## Senses

### 1. a contributing influence

noun · CEFR B1 · Academic

one of the things that helps produce a result or influence a situation.

For teachers: a circumstance, fact, or influence that contributes to a specific result or outcome.

- Cost was the most important factor in their decision to move house.
- Environmental factors, such as soil quality and annual rainfall, significantly influence the crop yield in this specific region.

Usage: Often used with the preposition 'in'.

### 2. mathematics

noun · CEFR B2 · Technical

a number that divides into another number exactly.

For teachers: a whole number that divides exactly into another number without leaving a remainder.

- The factors of six are one, two, three, and six.
- To simplify the fraction, the students first had to identify the greatest common factor of the numerator and the denominator.

### 3. business agent

noun · CEFR C1 · Technical · Formal

a person or company that does business for another, especially by buying debts.

For teachers: a commercial agent who buys and sells goods for others on commission, or a firm that buys accounts receivable at a discount.

- The company used a factor to collect money from customers who had not paid.
- By selling their outstanding invoices to a factor, the small business was able to improve its immediate cash flow despite the high fees.

### 4. estate manager

noun · CEFR C2 · British English · Dialect

a person who manages a large farm or area of land for the owner.

For teachers: a person employed to manage an estate or farm; a land steward.

- The factor visited the farmers to collect the rent for the landlord.
- In rural Scotland, the estate factor traditionally acted as the primary intermediary between the tenant farmers and the distant landowner.

Teaching tip: This sense is primarily found in Scottish contexts or historical literature.

### 5. to calculate factors

verb · CEFR B2 · Technical

to find the numbers that multiply together to make a specific number.

For teachers: to resolve a number or expression into its constituent factors.

- It is easy to factor the number ten into two and five.
- The encryption algorithm relies on the fact that it is computationally difficult to factor extremely large prime numbers.

### 6. to include in a plan

verb · CEFR B2

to include something in your calculations or plans.

For teachers: to include a particular fact or situation when you are thinking about or planning something.

- We need to factor in the cost of petrol for our road trip.
- When calculating the project timeline, the manager failed to factor in the potential for delays caused by the national holiday.

Usage: Almost always used as the phrasal verb 'factor in' or 'factor out'.

## Examples

- Price is the most important factor when I buy a car.
- The committee identified poor communication as a major factor in the project's failure last month.
- While economic growth is a significant factor in social stability, researchers must also consider cultural shifts and demographic changes to form a complete picture of the region's development.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.