parameter

noun
pa·​ram·​e·​ter | \ pə-ˈra-mə-tər How to pronounce parameter (audio) \

Definition of parameter

1a : an arbitrary constant whose value characterizes a member of a system (such as a family of curves) also : a quantity (such as a mean or variance) that describes a statistical population
b : an independent variable used to express the coordinates of a variable point and functions of them — compare parametric equation
2 : any of a set of physical properties whose values determine the characteristics or behavior of something parameters of the atmosphere such as temperature, pressure, and density
3 : something represented by a parameter : a characteristic element broadly : characteristic, element, factor political dissent as a parameter of modern life health care is a universal parameter, … a ubiquitous concern across every age, occupation, and class line. — Wayne Biddle
4 : limit, boundary usually used in plural the parameters of science fictionThe investigation stayed within the parameters set by the court.

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Other Words from parameter

parametric \ ˌper-​ə-​ˈme-​trik How to pronounce parametric (audio) , ˌpa-​rə-​ \ adjective
parametrically \ ˌper-​ə-​ˈme-​tri-​k(ə-​)lē How to pronounce parametrically (audio) , ˌpa-​rə-​ \ adverb

Parameter vs. Perimeter

It's very easy to confuse parameter with perimeter. Not only do the two words sound the same, they both connote a boundary or limit.

When parameter is used to mean "a boundary or limit," it is usually in its plural form, and often as the object of a preposition such as within or beyond:

Let's face it, managing weight loss or maintenance can be trying enough within the parameters of a daily routine.
Geoff Kerr, Weight Watchers, November 1991

Though candor sometimes encourages Bruno to "stray beyond the parameters of good taste," his interaction with Lydia is always convincingly portrayed as a loving, tender relationship.
Ron Charles, The Washington Post, 8 Feb. 2011

In geometry, perimeter refers to the boundary of a closed plane figure. You might remember calculating perimeters in school. If each side of an equilateral triangle measures 9 feet, then the perimeter of the triangle measures 27 feet. In more general use, perimeter describes an outer stretch, as in "The college president lived in a house on the perimeter of the campus."

Parameter originally had a meaning pertaining to mathematics as well. The dictionary defines it as "an arbitrary constant whose value characterizes a member of a system (as a family of curves); also : a quantity (as a mean or variance) that describes a statistical population" as well as "an independent variable used to express the coordinates of a variable point and functions of them."

Some twentieth-century usage commentators objected to the use of a scientific-sounding word like parameter in general contexts (as in the examples above), especially to mean "a limit or boundary," theorizing that perimeter must have been what the speaker or writer intended.

However, perimeter was not often used in the phrasings that parameter is used in (that is, as the object of within or beyond) until much later. In fact, a word such as bounds or range or confines often serves as a more appropriate equivalent for parameter than the marginal connotations of perimeter:

But a true novel is an extended piece of fiction: Length is clearly one of its parameters.
Anthony Burgess, The New York Times Book Review, 5 Feb. 1984

Shields will then subsume that request in the overall City operating budget that he will recommend to the City Council in mid-March, and the Council will make its final decisions on the parameters of the budget, including any tax increases or cuts, by the end of April.
Nicholas F. Benton, The Falls Church News Press, 6 Jan. 2016

Examples of parameter in a Sentence

Recent Examples on the Web

The amended budget sets even tighter parameters for negotiations between Mr. Cuomo and state legislators over the coming weeks. Jimmy Vielkind, WSJ, "Tax Shortfalls Widen New York’s Revenue Gap," 16 Feb. 2019 On its own, this model could take a wide variety of behaviors, depending on the values chosen for some of its parameters. John Timmer, Ars Technica, "Atoms may come apart as the Universe’s biggest stars explode," 24 Oct. 2018 Each of these 15 neurons has a weight parameter for each of its 784 inputs. Timothy B. Lee, Ars Technica, "How computers got shockingly good at recognizing images," 18 Dec. 2018 And Level 4 / 5 describes the top two levels of vehicle automation as defined by the Society of Automotive Engineers: Level 4 is no human driver within certain parameters; and Level 5 is no human driver without restrictions. Andrew J. Hawkins, The Verge, "Volkswagen, Intel, and Mobileye will launch a self-driving taxi service in Israel in 2019," 29 Oct. 2018 The congressional debate begins later this month, with committee hearings scheduled for Feb. 26-27 aimed at framing the broad parameters for possible privacy legislation. John D. Mckinnon, WSJ, "Partisan Rift Threatens Federal Data-Privacy Law," 17 Feb. 2019 That means this layer alone has 15×784=11,760 weight parameters. Timothy B. Lee, Ars Technica, "How computers got shockingly good at recognizing images," 18 Dec. 2018 The actuator was showing temperatures falling during the day and rising at night, each one outside of normal parameters. David Grossman, Popular Mechanics, "An Unexpected Component Helped Curiosity Observe a Martian Dust Storm," 27 Sep. 2018 Memphis came to a 30-day agreement with Bird to set parameters for operation while the city put its regulations into place. Ethan May, Indianapolis Star, "Another dockless scooter service launching Saturday in Indianapolis," 22 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'parameter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of parameter

1833, in the meaning defined at sense 1a

History and Etymology for parameter

New Latin, from para- + Greek metron measure — more at measure

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Last Updated

11 Apr 2019

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Time Traveler for parameter

The first known use of parameter was in 1833

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More Definitions for parameter

parameter

noun

English Language Learners Definition of parameter

: a rule or limit that controls what something is or how something should be done

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More from Merriam-Webster on parameter

Rhyming Dictionary: Words that rhyme with parameter

Spanish Central: Translation of parameter

Nglish: Translation of parameter for Spanish Speakers

Britannica English: Translation of parameter for Arabic Speakers

Britannica.com: Encyclopedia article about parameter

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