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

Derived Forms

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

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

Voters are “hungry for a different future for this city — one that is affordable, functional, creative, and safe,” Raman said in a statement.

From Los Angeles Times • Jun. 1, 2026

Drug candidate bepirovirsen helped nearly a fifth of patients in two late-stage clinical trials achieve a functional cure, the company said.

From The Wall Street Journal • May 28, 2026

The findings suggest that in multiple sclerosis, myelin-producing cells may come under stress and revert to a younger, less functional state instead of dying completely.

From Science Daily • May 27, 2026

If astronauts do not do exercise, they also lose coordination and cardiovascular fitness, they become less able to carry out the functional tasks that they're required to do.

From BBC • May 22, 2026

It was the first in a sequence of impossibly rich and voluminous banquets whose menus raised the question of whether any of the city’s leading men could possibly have a functional artery.

From "The Devil in the White City" by Erik Larson

Related Words

• practical
• useful
• utilitarian