parameter

American  

[puh-ram-i-ter] / pəˈræm ɪ tər /

noun

• parameters
  plural

1. Mathematics.

   1. a constant or variable term in a function that determines the specific form of the function but not its general nature, as a in f (x ) = ax, where a determines only the slope of the line described by f (x ).

   2. one of the independent variables in a set of parametric equations.

2. Statistics. a variable entering into the mathematical form of any distribution such that the possible values of the variable correspond to different distributions.

3. Computers. a variable that must be given a specific value during the execution of a program or of a procedure within a program.

4. Usually parameters. limits or boundaries; guidelines.

   the basic parameters of our foreign policy.

5. characteristic or factor; aspect; element.

   a useful parameter for judging long-term success.

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parameter British  

/ pəˈræmɪtə /

noun

1. one of a number of auxiliary variables in terms of which all the variables in an implicit functional relationship can be explicitly expressed See parametric equations

2. a variable whose behaviour is not being considered and which may for present purposes be regarded as a constant, as y in the partial derivative ∂f( x,y )/∂ x

3. statistics a characteristic of the distribution of a population, such as its mean, as distinct from that of a sample Compare statistic

4. informal any constant or limiting factor

   a designer must work within the parameters of budget and practicality

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parameter Cultural  

1. A quantity or number on which some other quantity or number depends. An informal example is, “Depending on the traffic, it takes me between twenty minutes and an hour to drive to work”; here, “traffic” is the parameter that determines the time it takes to get to work. In statistics, a parameter is an unknown characteristic of a population — for example, the number of women in a particular precinct who will vote Democratic.

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Usage

Some object strongly to the use of parameter in these newer senses. Nevertheless, the criticized uses are now well established both in educated speech and in edited writing.

Discover More

The term is often mistakenly used to refer to the limits of possible values a variable can have because of confusion with the word perimeter.

Other Word Forms

Derived Forms

• parametric
  adjective
• parametrical
  adjective

Inflected Forms

Nouns

• parameters
  plural

Etymology

Origin of parameter

From the New Latin word parametrum, dating back to 1650–60; see para- ¹, -meter

Explanation

A parameter is a limit. In mathematics a parameter is a constant in an equation, but parameter isn’t just for math anymore: now any system can have parameters that define its operation. You can set parameters for your class debate. Parameter comes from a combination of the Greek word para-, meaning “beside,” and metron, meaning “measure.” The natural world sets certain parameters, like gravity and time. In court, the law defines the parameters of legal behavior. Parameter and perimeter are similar, but a perimeter is the physical distance around an object, while a parameter can contain or define something either physically or abstractly.

Example Sentences

See Examples For:

parameter parameters

Then, pick activities that fit within that parameter.

From MarketWatch ● Sep. 17, 2026

They also note that every parameter in the VLE carries significant uncertainty, much like the Drake Equation.

From Science Daily ● Jun. 26, 2026

"In standard quantum mechanics, time is treated as an external, classical parameter that is not affected by the quantum system being studied," explains Curceanu.

From Science Daily ● May 3, 2026

“The exchange rate is not a trigger parameter for the ECB.”

From The Wall Street Journal ● Mar. 2, 2026

So they use parameter to mean a boundary, a characteristic, a component, an element, a feature, an ingredient, a part, a perimeter, a quality, or a requirement.

From "Woe Is I" by Patricia T. O'Conner

Open AI models are, by definition, harder to control, as users can alter their parameters -- potentially for malicious purposes.

From Barron's ● Sep. 13, 2026

"No matter how sophisticated your controllers, in the end it's a human operator that sets the parameters for that control," Farre Kaga said.

From Science Daily ● Sep. 6, 2026

Next time you offer to buy someone drinks — or anything, really — set the parameters first.

From MarketWatch ● Sep. 2, 2026

Tencent released its Hy4 preview on Friday, more than doubling the previous generation’s parameters, although still smaller than those by peers such as Alibaba’s Qwen3.8-Max and Moonshot’s Kimi K3.

From The Wall Street Journal ● Aug. 31, 2026

“Filling the refrigerator does not fall within the parameters of my responsibilities. Therefore, the lack of food therein would have no reflection upon me whatsoever.”

From "Fish in a Tree" by Lynda Mullaly Hunt

Related Words

• criterion
• framework
• guideline
• restriction
• specification