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

Example Sentences

The case is taking place in a remodelled conference hall that cost hundreds of thousands of euros and Mitsotakis has said it is "among the most functional and modern in Europe".

From BBC • Apr. 1, 2026

The site is roughly 100 miles southwest of the nation’s only fully functional rare earths mine — Mountain Pass operated by MP Materials, in which the U.S.

From Los Angeles Times • Mar. 30, 2026

Older mice without functional Caspase-2 developed liver tumors far more often than normal mice.

From Science Daily • Mar. 23, 2026

Muscle growth and exploratory functional efficacy weren’t consistent nor robust enough to move the drug to late-stage development, the company said.

From The Wall Street Journal • Mar. 23, 2026

A functional circuit of genes was switched on and off, as if operated by a common spool or a master switch.

From "The Gene" by Siddhartha Mukherjee

Related Words

• practical
• useful
• utilitarian