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, ˌpærəˈmɛtrɪk /

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

AT&T’s own OTel model, which is an open model customized with telecom-specific data, was tested in 32 different variations of model type and parameter size, Markus said.

From The Wall Street Journal ● Aug. 12, 2026

"The millimeter and submillimeter radio bands remain almost completely unexplored for SETI, so this is really about opening up a new area of parameter space to search."

From Science Daily ● Jul. 30, 2026

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

From The Wall Street Journal ● Mar. 2, 2026

By the yardstick of its own goals, the nation’s second-largest school system is likely to fall short by nearly every parameter — taking in sample measures of literacy, math and social emotional learning.

From Los Angeles Times ● Jan. 15, 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

The Wyden document avoids specific parameters, which makes precise cost estimates difficult.

From The Wall Street Journal ● Aug. 11, 2026

The company will resume releasing models with open weights, meaning their parameters can be downloaded by anyone, something it paused after reorganizing its AI operations last year.

From The Wall Street Journal ● Aug. 10, 2026

Critics argued that it flew in the face of innocent-before-proven-guilty parameters and that the job of police was to investigate, not adjudicate.

From BBC ● Jul. 31, 2026

A model’s parameters are the variables it uses to learn and recognize patterns during training, and they serve as a sort of memory.

From MarketWatch ● Jul. 21, 2026

At the bottom of the Depression, when wrenching need narrowed the parameters of experience as never before, the liberation offered by the racehorse was, to young men like Pollard and Woolf, a siren song.

From "Seabiscuit: An American Legend" by Laura Hillenbrand

Related Words

• criterion
• framework
• guideline
• restriction
• specification