functional

American  

[fuhngk-shuh-nl] / ˈfʌŋk ʃə nl /

adjective

1. of or relating to a function or functions.

   functional difficulties in the administration.

2. capable of operating or functioning.

   When will the ventilating system be functional again?

3. having or serving a utilitarian purpose; capable of serving the purpose for which it was designed.

   functional architecture; a chair that is functional as well as decorative.

4. Also functionalistic (of a building or furnishing) constructed or made according to the principles of functionalism or primarily as a direct fulfillment of a material need.

5. Medicine/Medical. without a known organic cause or structural change.

   a functional disorder.

6. pertaining to an algebraic operation.

   a functional symbol.

7. Linguistics. (of linguistic analysis, language teaching, etc.) concerned with the communicative role of language rather than, in addition to, or as the framework for its formal structure.

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noun

1. Mathematics. a function that has a domain whose elements are functions, sets, or the like, and that assumes numerical values.

functional British  

/ ˈfʌŋkʃənəl /

adjective

1. of, involving, or containing a function or functions

2. practical rather than decorative; utilitarian

   functional architecture

3. capable of functioning; working

4. med affecting a function of an organ without structural change

5. psychol

   1. relating to the purpose or context of a behaviour

   2. denoting a psychosis such as schizophrenia assumed not to have a direct organic cause, like deterioration or poisoning of the brain Compare organic psychosis

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noun

1. maths a function whose domain is a set of functions and whose range is a set of functions or a set of numbers

Other Word Forms

• functionality
  noun
• hyperfunctional
  adjective
• multifunctional
  adjective
• nonfunctional
  adjective
• prefunctional
  adjective
• semifunctional
  adjective
• subfunctional
  adjective
• superfunctional
  adjective
• unfunctional
  adjective
• functionally
  adverb
• hyperfunctionally
  adverb
• nonfunctionally
  adverb
• semifunctionally
  adverb
• subfunctionally
  adverb
• unfunctionally
  adverb

Etymology

Origin of functional

First recorded in 1625–35; function + -al ¹

Explanation

Use the adjective functional to describe something that is made to do a specific job, such as the functional alarm clock feature on a digital stopwatch. The word functional comes from the Latin word functionem, meaning "performance, execution." It can also describe whether something is working properly. This is what shoppers at a garage sale want to be sure of before they leave with an old television — they plug it in to make sure it's functional. In this case the opposite of functional is useless.

Example Sentences

In Alibaba's case, the company argues that this restriction creates a functional blockade, forcing its long-term American advisers to sever ties to protect their own lucrative defence contracts.

From BBC • Jun. 23, 2026

At the end of another tumultuous day in Westminster it looks all but certain that it will now fall to him to fit all of this together into a cohesive government and functional political project.

From BBC • Jun. 22, 2026

Some of these variants continue to play functional roles in the human body.

From Science Daily • Jun. 14, 2026

“There are so many more objects that you can buy that are functional, high-end and gorgeous,” says Towle, whose firm does much redesign-and-renovation work for those 50 and up.

From The Wall Street Journal • Jun. 13, 2026

The curse of knowledge, in combination with chunking and functional fixity, helps make sense of the paradox that classic style is difficult to master.

From "The Sense of Style" by Steven Pinker

Related Words

• practical
• useful
• utilitarian