function

verb

functioned; functioning ˈfəŋ(k)-sh(ə-)niŋ How to pronounce function (audio)
Synonyms of functionnext

intransitive verb

1
: to have a function : serve
a couch that also functions as a bed
an attributive noun functions as an adjective
2
: to carry on a function or be in action : operate
The new machine functions well.
an immune system functioning normally

Examples of function in a Sentence

The new machine functions well. His bad health has prevented him from being able to function effectively in recent weeks. Her heart now seems to be functioning normally. The computer network is not yet fully functioning.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The other loft, meanwhile, is similarly laid out, but without the desk, and can function as either a second bedroom or additional storage space, depending on the owner's needs. New Atlas, 8 June 2026 Congress was never intended to function as an extension of the White House. The Editorial Board, Chicago Tribune, 8 June 2026 The SpotOn Nova Edition is designed to function as both a containment system and a training tool. Rachel Cortez, USA Today, 8 June 2026 Authorities said hospital operations had resumed and that major highways, markets and commercial centers were functioning normally by Monday. ABC News, 8 June 2026 See All Example Sentences for function

Word History

Etymology
First Known Use

1856, in the meaning defined at sense 1

Time Traveler
The first known use of function was in 1856

Browse Nearby Words

Cite this Entry

“Function.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/function. Accessed 9 Jun. 2026.

Kids Definition

function

1 of 2 noun
func·​tion ˈfəŋ(k)-shən How to pronounce function (audio)
1
: professional job or duties : occupation
2
a
: the particular purpose for which a person or thing is specially fitted or used or for which a thing exists
the function of a knife is cutting
b
: the natural or proper action of a bodily part in a living thing
the function of the heart
3
: a large important ceremony or social affair
4
a
: a mathematical relationship that assigns exactly one element of one set to each element of the same or another set
b
: something (as a quality, trait, or measurement) that is determined by or based on something else
height is a function of age in children
functionless adjective

function

2 of 2 verb
functioned; functioning -sh(ə-)niŋ How to pronounce function (audio)
: to serve a certain purpose : work

Medical Definition

function

1 of 2 noun
func·​tion ˈfəŋ(k)-shən How to pronounce function (audio)
1
: any of a group of related actions contributing to a larger action
especially : the specific contribution of a bodily part to the processes necessary for life in an organism
The function of the kidneys is to filter waste from the blood.
see vital function
2
: characteristic behavior of a chemical compound due to a particular reactive unit
functionless adjective

function

2 of 2 intransitive verb
functioned; functioning -sh(ə-)niŋ How to pronounce function (audio)
: to have a function
shivering functions to maintain the heat of the body

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