function

American  

[fuhngk-shuhn] / ˈfʌŋk ʃən /

noun

• functions
  plural

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.

3. a factor related to or dependent upon other factors.

   Price is a function of supply and demand.

4. Mathematics.

   1. 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 = x 2 ; operator.

   2. Also called multiple-value function. 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 y 2 = x 2 , which assigns to every x the two values y = + x and y = − x.

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

   4. a relationship in which an input value of a variable has a specifically calculated output value: for example, if the function of x is x 2 , the output will always be the square of whatever the value of x is. f, F

5. Geometry.

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

   2. hyperbolic function.

6. Grammar.

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

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

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

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verb (used without object)

• functions,
  present (3rd person singular)
• functioned,
  past participle,  past
• functioning
  present participle

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.

function British  

/ ˈfʌŋkʃən /

noun

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

3. a factor dependent upon another or other factors

   the length of the flight is a function of the weather

4. 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)

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verb

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

function Scientific  

/ fŭngk′shən /

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.

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function Cultural  

1. 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.

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Other Word Forms

Derived Forms

• prefunction
  noun
• subfunction
  noun
• superfunction
  noun
• refunction
  verb (used without object)
• functionless
  adjective
• interfunction
  adjective
• multifunction
  adjective
• nonfunctioning
  adjective
• overfunctioning
  adjective
• unfunctioning
  adjective
• well-functioning
  adjective

Inflected Forms

Nouns

• functions
  plural

Participles

• functioning
  present
• functioned
  past

Conjugated Forms

Present

• function
  simple
• functions
  simple
• have functioned
  perfect
• has functioned
  perfect
• am functioning
  progressive
• are functioning
  progressive
• is functioning
  progressive
• have been functioning
  perfect progressive
• has been functioning
  perfect progressive

Past

• functioned
  simple
• had functioned
  perfect
• was functioning
  progressive
• were functioning
  progressive
• had been functioning
  perfect progressive

Future

• will function
  simple
• will have functioned
  perfect
• will be functioning
  progressive
• will have been functioning
  perfect progressive

Etymology

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

Explanation

In the old "Schoolhouse Rock" song, "Conjunction junction, what's your function?," the word function means, "What does a conjunction do?" The famous design dictum "form follows function" tells us that an object's design should reflect what it does. Function is one of those words that gets used a lot and means lots of different things. It means what something does, but also what a person does, whether something or someone is doing what they should, and crazily enough, a big party. "Your function is to bring the senator coffee at the political function. He cannot function without it."

Example Sentences

See Examples For:

function functions functioned functioning

Jeff Hood: Well, none of them are good, but there are some that function certainly more systematically than others.

From Slate ● Oct. 7, 2026

Both companies plan to offer a commercial air taxi service using electric aircraft that function like Ubers over congested cities.

From Los Angeles Times ● Oct. 7, 2026

And while nature almost exclusively produces the version it requires to function, chemical reactions in a lab usually create a 50/50 mix of both left- and right-handed molecules.

From BBC ● Oct. 7, 2026

Earlier research from Blau's laboratory found that a molecule called prostaglandin E2 is important for the function of muscle stem cells.

From Science Daily ● Oct. 6, 2026

The “action” of a gene is described in mechanistic terms: genes encode chemical messages to build proteins that ultimately enable form and function.

From "The Gene" by Siddhartha Mukherjee

Mitochondria are often described as the powerhouses of the cell because they produce much of the energy our bodies need to grow, move, repair tissues, and carry out everyday functions.

From Science Daily ● Oct. 3, 2026

Your hand and forearm strength can be important to everyday functions, like opening a jar or turning a key in a difficult lock.

From The Wall Street Journal ● Oct. 1, 2026

If spending on administrative or non-healthcare functions exceeded 10% of total revenue, a clinic would have to pay a penalty equal to the amount it overspent.

From Los Angeles Times ● Oct. 1, 2026

For five months, the creatures will not eat or drink, slowing all bodily functions as they shelter away from the harsh Alaskan weather.

From Barron's ● Sep. 30, 2026

If, as I believe, the urge to make a kind of music is as much a characteristic of biology as our other fundamental functions, there ought to be an explanation for it.

From "The Lives of a Cell" by Lewis Thomas

Some also said her engagement party last fall functioned more as a commercial endeavor than a personal celebration, citing in part the affiliate links she posted beforehand for suggested guest attire.

From The Wall Street Journal ● Oct. 6, 2026

Because platinum conducts electricity, the lens also functioned as an electrode.

From Science Daily ● Sep. 29, 2026

At first, the account functioned like a group chat for local surfers.

From Los Angeles Times ● Sep. 14, 2026

Credit markets have functioned smoothly, heavy supply has been absorbed and the main AI issuers still are “elite corporations with incredible balance sheets.”

From MarketWatch ● Aug. 25, 2026

It was when all the rules by which the traditional economy had functioned were broken and remade.

From "Outliers" by Malcolm Gladwell

The Election Commission, a three-member body comprising the chief election commissioner and two election commissioners, defended its decision-making process, saying differing views were part of institutional functioning and that decisions had ultimately been taken unanimously.

From BBC ● Oct. 6, 2026

“A sufficiently powerful system functioning within a self-reinforcing loop risks reducing the ability of society to exercise meaningful oversight and intervention,” Bailey wrote.

From The Wall Street Journal ● Sep. 30, 2026

Scientists had long assumed that having at least one functioning version of this system was essential for cellular life.

From Science Daily ● Sep. 25, 2026

"Rapid alerts about missile and drone threats are essential - they save lives. This is critical civilian infrastructure... It is not a military target. It is essential to keeping everyday life functioning," Sybiha said.

From BBC ● Sep. 25, 2026

After all, Hamilton reasoned, the government would not automatically cease functioning if an enemy army captured the capital.

From "An American Plague: The True and Terrifying Story of the Yellow Fever Epidemic of 1793" by Jim Murphy

Related Words

• action
• activity
• affair
• behavior
• business
• duty
• exercise
• objective
• operation
• part
• power
• purpose
• responsibility
• role
• service
• situation
• task
• work