coefficient

American  

[koh-uh-fish-uhnt] / ˌkoʊ əˈfɪʃ ənt /

noun

1. Mathematics. a number or quantity placed (generally) before and multiplying another quantity, as 3 in the expression 3x.

2. Physics. a number that is constant for a given substance, body, or process under certain specified conditions, serving as a measure of one of its properties.

   coefficient of friction.

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adjective

1. acting in consort; cooperating.

coefficient British  

/ ˌkəʊɪˈfɪʃənt /

noun

1. maths

   1. a numerical or constant factor in an algebraic term

      the coefficient of the term 3xyz is 3

   2. the product of all the factors of a term excluding one or more specified variables

      the coefficient of x in 3axyz is 3ayz

2. physics a value that relates one physical quantity to another

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coefficient Scientific  

/ kō′ə-fĭsh′ənt /

1. A number or symbol multiplied with a variable or an unknown quantity in an algebraic term. For example, 4 is the coefficient in the term 4 x, and x is the coefficient in x (a + b).

2. A numerical measure of a physical or chemical property that is constant for a system under specified conditions. The speed of light in a vacuum, for example, is a constant.

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Other Word Forms

• coefficiently adverb

Etymology

Origin of coefficient

First recorded in 1655–65, coefficient is from the New Latin word coefficient- (stem of coefficiēns ). See co-, efficient

Explanation

In math and science, a coefficient is a constant term related to the properties of a product. In the equation that measures friction, for example, the number that always stays the same is the coefficient. In plain English, coefficient means "joining together to produce a result." Sometimes people use the word to talk about social phenomena, like the coefficient factors of vanity and self-loathing in a celebrity's alcoholic demise. But mostly you'll encounter it in math and science. In algebra, the coefficient is the number that you multiply a variable by, like the 4 in 4x=y. In chemistry, when you see a number in front of a chemical like 2H2o, you're looking at the coefficient.

Example Sentences

The place reserved for the Champions League titleholders will pass to the league champions in qualifying with the best Uefa coefficient.

From BBC • Apr. 8, 2026

The correlation coefficient for all rolling four-month periods since 1926 is slightly negative — meaning there’s a slightly greater-than-even chance that four-month relative strength will be followed by four months of relative weakness.

From MarketWatch • Jan. 30, 2026

According to Kim, people often think first of Pearson's correlation coefficient when they hear the word agreement, since it is introduced early in statistics education and remains a fundamental tool.

From Science Daily • Nov. 14, 2025

However, standard measures of income inequality, such as the Gini coefficient, changed little over the period.

From The Wall Street Journal • Nov. 12, 2025

The series of equations we needed to work described the parameters of thrust coefficient, nozzle-throat area, combustion-chamber cross-sectional areas, and velocity of the gases predicted for any particular propellant.

From "October Sky" by Homer Hickam

Related Words

• collegial
• concerted
• coordinated
• harmonious
• interdependent
• reciprocal
• symbiotic
• united