- present participle of function.
functioning
Americanadjective
-
performing a specified action or activity; working; operating.
My son has only one functioning kidney.
-
(of a person with addiction or other illness or disability) able to cope with everyday life, as at home or at work: functioning diabetics.
a functioning alcoholic with a successful career;
functioning diabetics.
Etymology
Origin of functioning
First recorded in 1835–40; in 1970–75 functioning for def. 2; function ( def. ) (in the sense “to perform an action”) + -ing 2 ( def. )
Explanation
Something that is functioning is working — doing what it's supposed to do. A functioning refrigerator keeps your food cold. A functioning television shows a clear picture. A functioning group gets things done in an orderly and timely fashion. A function is the purpose that something is made for. A flashlight's function is to light up. But if it's not functioning, or working properly, you might need to change its batteries or buy a new one. If your car can get you from point A to point B but the engine sounds like it's going to die any minute, you might say that it is "barely functioning." Sometimes people use the word functional to mean the thing as functioning.
Vocabulary lists containing functioning
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
“A sufficiently powerful system functioning within a self-reinforcing loop risks reducing the ability of society to exercise meaningful oversight and intervention,” Bailey wrote.
From The Wall Street Journal ● Sep. 30, 2026
Cooper said some developments had even featured "fake" weep vents, where decorative plastic pieces had been fitted instead of functioning openings.
From BBC ● Sep. 26, 2026
"No living organism or cell had ever been found that could live without having a functioning disulfide reductase system."
From Science Daily ● Sep. 25, 2026
Seeley and his colleagues demonstrated how personality is, at least partly, brought into being by neurons that are specifically tailored to synthesize social functioning.
From The Wall Street Journal ● Sep. 18, 2026
“She’s in with the respiratory therapists right now. They’re running tests to see how her lungs are functioning and whether she can be weaned off the ventilator.”
From "If I Stay" by Gayle Forman
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
