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

Eddie Bauer Men’s Rainier Pants Durable, flattering, and multi-functional, the Eddie Bauer Rainier Pants are a must for active travelers looking to hike, sightsee, and more–all in one trip. —Merrell Readman, Travel + Leisure, 27 Dec. 2025

Unique lighting, like these color-changing string lights and globe garden lights, is a fun and functional addition to a front or backyard. —Gabriela Izquierdo, Southern Living, 26 Dec. 2025

Beef up your cold-weather wardrobe with functional layers like this classic crewneck sweater made from a cashmere-blend or this Levi’s jacket that’s lined with plush teddy fleece. —Clara McMahon, PEOPLE, 26 Dec. 2025

While the arrest did cause severe kidney and liver damage, ECMO afforded a long enough runway for dialysis and other treatments that gradually brought those vital organs back into functional condition. —Paul Sisson, San Diego Union-Tribune, 25 Dec. 2025

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