English Reference

Word

function

Phoneticsfunc·tion, stress on the first syllable

US/ˈfəŋkʃən/

UK/fˈʌŋkʃən/

Definitions

01purpose or use

B1 · Intermediate Countable noun

n. the natural purpose or job of something.

n. the natural purpose of a thing or the specific duty of a person.

“The main function of the heart is to pump blood around the body.”

“The architect argued that the building's aesthetic form should be secondary to its primary function as a community hub.”

Synonyms

02formal event

B2 · Upper Intermediate Countable noun Formal

n. a large, formal party or official meeting.

n. a large or formal social event or official ceremony.

“He had to wear a suit to the charity function at the town hall.”

“The embassy hosted a formal function to celebrate the signing of the new trade agreement between the two nations.”

03math/computing

B2 · Upper Intermediate Countable noun Computing Technical

n. a rule that relates one amount to another, or a set of instructions in a computer program.

n. a relationship where each input has a single output, or a named section of code that performs a specific task.

“The programmer wrote a new function to calculate the total price automatically.”

“In functional programming, a pure function must return the same output for the same input without causing side effects.”

04result of something

C1 · Advanced Countable noun Academic

n. something that happens as a direct result of something else.

n. a variable or factor that depends on and varies with another.

“Success is often a function of hard work and a bit of luck.”

“The researcher noted that the rate of decay was a direct function of the ambient temperature in the laboratory.”

05to serve as

B2 · Upper Intermediate

v. to do the job of something else.

v. to serve a particular purpose or fulfill a specific role. Usually followed by the preposition 'as'.

“During the summer, the sofa functions as a bed for guests.”

“In many ancient societies, myths functioned as a way to explain natural phenomena that were not yet understood by science.”

Synonyms

Collocations

Common phrases and expressions where native English speakers use the word “function” in context.

Verb

01. effectively function

“The team needs a clear leader to effectively function during the crisis.”

adv + verb

02. independently function

“The new software module can independently function without the main program.”

adv + verb

03. normally function

“After the repairs, the engine began to normally function again.”

adv + verb

Adjective

04. critical function

“Maintaining a steady temperature is a critical function of the cooling system.”

adj + noun

05. important function

“Education serves an important function in modern society.”

adj + noun

06. primary function

“The primary function of the heart is to pump blood around the body.”

adj + noun

07. social function

“The club is hosting a social function to welcome new members next week.”

adj + noun

08. specific function

“Each button on the remote control has a specific function.”

adj + noun

Real-World Examples

“The system creates a watermark on protein sequences themselves without compromising the protein’s function.”
Ars Technica 30 Sept 2026
“It involves weaving a faint statistical tell into both the amino-acid sequence and 3D shape of computer-designed proteins — without noticeably compromising their function.”
Nature 30 Sept 2026

Etymology

From Middle French function, from Old French fonction, from Latin functiō (“performance, execution”), from functus, perfect participle of fungor (“to perform, execute, discharge”), from Proto-Indo-European *bʰewg- (“to enjoy”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Synonyms

Word family

Domains

AnthropologyBiologyChemistryComputingLogicMathematics

This entry

Exam level
CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.B1 PreliminaryIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.4.0–5.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 3.0–3.544–71TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.550–784
Frequency
Common
Level
B1 · IntermediateOxford
Updated

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