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

Intel’s manufacturing yields—the ratio of functional chips to the maximum possible—in its newest chip-making process are too low.

From Barron's • Apr. 14, 2026

Lee had to make sure her left hand, among other body parts, was functional and that her balance and movement bounced back.

From Los Angeles Times • Apr. 14, 2026

"The resources Meta is devoting to blocking these ads would be better spent improving user safety through functional tools to reduce problematic use and to detect and remove users under age 13," she added.

From BBC • Apr. 10, 2026

The researchers describe this system as a "pseudo-organelle," a functional compartment that is not enclosed by a membrane but still plays a major role in organizing cell behavior.

From Science Daily • Apr. 1, 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