# function

/ˈfəŋkʃən/ (US) · /fˈʌŋkʃən/ (UK)

Source: https://englishreference.com/word/function
Updated: 2026-07-22

## Senses

### 1. purpose or use

noun · CEFR B1

the natural purpose or job of something.

For teachers: 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.

### 2. formal event

noun · CEFR B2 · Formal

a large, formal party or official meeting.

For teachers: 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.

### 3. math/computing

noun · CEFR B2 · Technical

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

For teachers: 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.

### 4. result of something

noun · CEFR C1 · Academic

something that happens as a direct result of something else.

For teachers: 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.

### 6. to serve as

verb · CEFR B2

to do the job of something else.

For teachers: 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.

## Examples

- The main function of the heart is to pump blood.
- The new software update adds a search function that makes it much easier to find old messages.
- Although the architectural design is visually striking, the building's primary function as a hospital requires that aesthetic choices never compromise patient care or medical efficiency.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.