demon
noun
an evil spirit; devil or fiend.
demon
1 American
[dee-muhn]
/ ˈdi mən /
noun
-
demons
plural
-
an evil spirit; devil or fiend.
-
an evil passion or influence.
-
a person considered extremely wicked, evil, or cruel.
-
a person with great energy, drive, etc..
He's a demon for work.
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a person, especially a child, who is very mischievous.
His younger son is a real little demon.
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Australian Slang. a policeman, especially a detective.
adjective
-
of, pertaining to, characteristic of, or noting a demon.
-
possessed or controlled by a demon.
demon-
2
American
demon
British
/ ˈdiːmən /
noun
-
an evil spirit or devil
-
a person, habit, obsession, etc, thought of as evil, cruel, or persistently tormenting
-
Also called: daemon. daimon. an attendant or ministering spirit; genius
the demon of inspiration
-
-
a person who is extremely skilful in, energetic at, or devoted to a given activity, esp a sport
a demon at cycling
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( as modifier )
a demon cyclist
-
-
a variant spelling of daemon
-
informal a detective or policeman
-
computing a part of a computer program, such as a help facility, that can run in the background behind the current task or application, and which will only begin to work when certain conditions are met or when it is specifically invoked
Usage
What does demon- mean? Demon- is a combining form used like a prefix meaning “demon.” It is used in a few technical terms, especially in theology. Demon- comes from the Greek daimónion, meaning “thing of divine nature” and ultimate source of the English word demon. Among Jewish and Christian writers, daimónion was used to mean “evil spirit.”Demon- is a variant of demono-, which loses its -o- when combined with words or word elements beginning with vowels. Want to know more? Read our Words That Use demono- article.
Other Word Forms
Noun Inflected Forms
Etymology
Origin of demon
1350–1400; Middle English < Latin daemonium < Greek daimónion, thing of divine nature (in Jewish and Christian writers, evil spirit), neuter of daimónios, derivative of daímōn; demon ( def. 6 ) < Latin; see daemon
Explanation
A demon is an evil, mythical monster or spirit. Stories about demons are featured in a variety of different religious traditions. You might come across a demon in a supernatural fairy tale, or even in the Christian Bible. Demons are often interchangeable with devils, and both words are sometimes used to talk about a cruel, fiendish person. If you're extremely good at something, you also might be described as a demon: "She's a demon at bowling." The Greek root, daimon, doesn't have the same negative connotations — it means "spirit or deity."
Vocabulary lists containing demon
The House of Hades
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"Making Faces"
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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.
See Examples For:
When the thing dies, the worms fall away to reveal that it wasn’t always a demon, but a boar god felled by a dark force.
From Salon ● Jul. 22, 2026
"You will see a change in behaviour... a different consciousness. Something else takes over a person," Syquia said, noting he had personally exorcised a demon only a week earlier.
From Barron's ● Jul. 19, 2026
But to put the healthcare demon in context: According to federal government data, average annual healthcare costs for those over 65 are currently less than $8,000 a year per person.
From MarketWatch ● Jul. 17, 2026
The work also builds on the famous 19th century thought experiment known as "Maxwell's demon."
From Science Daily ● Jul. 3, 2026
If a tree falls in the forest and crushes a demon, does the tree get cursed?
From "The House of Hades" by Rick Riordan
“Supernatural,” the demon- and monster-hunting drama that will not die, is back for the 13th season.
From Los Angeles Times ● Oct. 6, 2017
Kyle Green of Wasilla got $49,300 to build a demon- stration solar house suitable for northern latitudes.
From Time Magazine Archive
His purpose in healing was not alone to restore health, but to demon- strate his divine Principle.
From Science and Health, with Key to the Scriptures by Mary Baker Eddy
The hour has struck when proof and demon- 342:3 stration, instead of opinion and dogma, are summoned to the support of Christianity, "making wise the simple."
From Science and Health, with Key to the Scriptures by Mary Baker Eddy
The Principle of divine metaphysics 111:12 is God; the practice of divine metaphysics is the utiliza- tion of the power of Truth over error; its rules demon- strate its Science.
From Science and Health, with Key to the Scriptures by Mary Baker Eddy
But in “Event Horizon,” Neill avoids hokeyness in what could otherwise be an extremely hokey film, finding the emotional center in a character whose inner demons become real-life manifestations of Hell.
From Salon ● Jul. 17, 2026
His Othello is hounded into a betrayal of his probity and hard-earned honor not just by the villainy of Iago but by the demons of his past.
From The Wall Street Journal ● Jul. 9, 2026
For Episode 6, Deming made great use of a small lab set, where Reilly wrestles with emotional demons after being drugged.
From Los Angeles Times ● Jun. 16, 2026
Then, 12 years later, Bosnia overcame their play-off demons by beating Wales and then Italy on penalties having trailed to both.
From BBC ● Jun. 12, 2026
Though Abigail was with him all the way, for Adams himself it was the supreme collaboration with his own private demons and doubts, his personal declaration of independence.
From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis
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.
