functional

adjective

func·​tion·​al ˈfəŋ(k)-sh(ə-)nəl 

1

a

: of, connected with, or being a function

the functional differences between the departments

b

: affecting physiological or psychological functions but not organic structure

functional heart disease

2

: used to contribute to the development or maintenance of a larger whole

functional and practical school courses

also : designed or developed chiefly from the point of view of use

The design of the building is not only functional but also beautiful.

3

: performing or able to perform a regular function

The flashlight was still functional after I had dropped it.

functionally

ˈfəŋ(k)-sh(ə-)nə-lē 

adverb

Synonyms of functional

• operational
• operating
• operative
• functioning

Examples of functional in a Sentence

The building's design is not only functional but also beautiful.

The flashlight was still functional after I dropped it.

The computer network is fully functional.

Recent Examples on the Web

The best custom home designs include ventilation fans that exhaust odor outside, making the enclosure functional for the cat and invisible to everyone else. — Ryan Brennan, Sacbee.com, 8 July 2026

The certification should describe the beneficiary's diagnosis, the nature of the functional limitations, the level of supervision or assistance required, and how those facts support the conclusion that the beneficiary meets the applicable test. — James Lange, Forbes.com, 8 July 2026

Buff combines conventional medicine with the latest in functional medicine. — Condé Nast, Condé Nast Traveler, 8 July 2026

Several others are only partially functional, with staff doctors and other frontline health workers among the victims of the disaster. — Durrie Bouscaren, NPR, 8 July 2026

Word History

First Known Use

1633, in the meaning defined at sense 1a

Phrases Containing functional

• functional calculus
• functional food
• functional genomics
• functional group
• functional illiterate
• functional magnetic resonance imaging
• functional shift

Rhymes for functional

• junctional
• bifunctional
• dysfunctional
• nonfunctional

Kids Definition

functional

adjective

func·​tion·​al ˈfuŋ(k)-shnəl 

-shən-ᵊl

1

a

: of, connected with, or being a function

b

: affecting bodily functions but not structure

functional heart disease

2

: designed or developed chiefly from the point of view of use

functional clothes

functional writing

3

: performing or able to perform a regular function

functionally

-shnə-lē 

-shən-ᵊl-ē

adverb

Medical Definition

functional

adjective

func·​tion·​al ˈfəŋ(k)-shnəl, -shən-ᵊl 

1

a

: of, connected with, or being a function compare structural sense 1

b

: affecting physiological or psychological functions but not organic structure

functional heart disease

a functional psychosis

compare organic sense 1b

2

: performing or able to perform a regular function

functionally

-ē 

adverb