[ fuhngk-shuhn ]
See synonyms for: functionfunctionedfunctioningfunctions on

  1. the kind of action or activity proper to a person, thing, or institution; the purpose for which something is designed or exists; role.

  2. any ceremonious public or social gathering or occasion.

  1. a factor related to or dependent upon other factors: Price is a function of supply and demand.

  2. Mathematics.

    • Also called correspondence, map, mapping, transformation. a relation between two sets in which one element of the second set is assigned to each element of the first set, as the expression y = x2; operator.

    • Also called mul·ti·ple-val·ue func·tion [muhl-tuh-puhl-val-yoo fuhngk-shuhn]. /ˈmʌl tə pəlˈvæl yu ˈfʌŋk ʃən/. a relation between two sets in which two or more elements of the second set are assigned to each element of the first set, as y2 = x2, which assigns to every x the two values y = +x and y = −x.

    • a set of ordered pairs in which none of the first elements of the pairs appears twice.

    • a relationship in which an input value of a variable has a specifically calculated output value: for example, if the function of x is x2, the output will always be the square of whatever the value of x is. Abbreviations: f, F

  3. Geometry.

    • a formula expressing a relation between the angles of a triangle and its sides, as sine or cosine.

  4. Grammar.

    • the grammatical role a linguistic form has or the position it occupies in a particular construction.

    • the grammatical roles or the positions of a linguistic form or form class collectively.

  5. Sociology. the contribution made by a sociocultural phenomenon to an ongoing social system.

verb (used without object)
  1. to perform a specified action or activity; work; operate: The computer isn't functioning now. He rarely functions before noon.

  2. to have or exercise a function; serve: In earlier English the present tense often functioned as a future. This orange crate can function as a chair.

Origin of function

First recorded in 1525–35; from Latin functiōn- (stem of functiō ) “a performance, execution,” equivalent to funct(us) (past participle of fungī ) “performed, executed” + -iōn--ion

Other words from function

  • in·ter·func·tion, adjective
  • mul·ti·func·tion, adjective
  • non·func·tion·ing, adjective
  • o·ver·func·tion·ing, adjective
  • pre·func·tion, noun
  • re·func·tion, verb (used without object)
  • sub·func·tion, noun
  • su·per·func·tion, noun
  • un·func·tion·ing, adjective
  • well-func·tion·ing, adjective

Words Nearby function Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use function in a sentence

British Dictionary definitions for function


/ (ˈfʌŋkʃən) /

  1. the natural action or intended purpose of a person or thing in a specific role: the function of a hammer is to hit nails into wood

  2. an official or formal social gathering or ceremony

  1. a factor dependent upon another or other factors: the length of the flight is a function of the weather

  2. Also called: map, mapping maths logic a relation between two sets that associates a unique element (the value) of the second (the range) with each element (the argument) of the first (the domain): a many-one relation. Symbol: f(x) The value of f(x) for x = 2 is f(2)

  1. to operate or perform as specified; work properly

  2. (foll by as) to perform the action or role (of something or someone else): a coin may function as a screwdriver

Origin of function

C16: from Latin functiō, from fungī to perform, discharge

Derived forms of function

  • functionless, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for function


[ fŭngkshən ]

  1. A relationship between two sets that matches each member of the first set with a unique member of the second set. Functions are often expressed as an equation, such as y = x + 5, meaning that y is a function of x such that for any value of x, the value of y will be 5 greater than x.

  2. A quantity whose value depends on the value given to one or more related quantities. For example, the area of a square is a function of the length of its sides.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for function


In mathematics, a quantity whose value is determined by the value of some other quantity. For example, “The yield of this field is a function of the amount of fertilizer applied” means that a given amount of fertilizer will yield an amount of whatever crop is growing.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.