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.
-
a person, especially a child, who is very mischievous.
His younger son is a real little demon.
-
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:
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 person in the diocese comes to fear that they or their loved one has been bodily possessed by a demon, the diocese launches an investigation involving medical, psychological, and psychiatric testing.
From Slate ● Jun. 8, 2026
In fourth place with $5.6 million was "Lee Cronin's The Mummy," an original horror flick from Warner Bros about a young girl possessed by a demon in an ancient mummification ritual.
From Barron's ● Apr. 26, 2026
Whatever this was, whatever demon wore her face, it wasn’t her.
From "Night Owls" by A.R. Vishny
“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
And yet these sons demon- strated the errors of their parents.
From The Works of Robert G. Ingersoll, Vol. 5 (of 12) Dresden Edition?Discussions by Ingersoll, Robert Green
As a divine student he unfolded God to man, illustrating and demon- 117:18 strating Life and Truth in himself and by his power over the sick and sinning.
From Science and Health, with Key to the Scriptures by Eddy, Mary Baker
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 Eddy, Mary Baker
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
Bowling an immaculate line and using the demons in the pitch, Archer unnerved Devon Conway with a blow to the helmet and, four balls later, had the left-hander fend to second slip.
From BBC ● Jun. 27, 2026
As Ms. Fletcher observes, such images suggest that guns were no longer perceived as “the weapon of demons, but of angels.”
From The Wall Street Journal ● Jun. 19, 2026
Still, 51-year-old Rhys didn’t take Nile’s demons or Tom’s supernatural burden home.
From Los Angeles Times ● Jun. 8, 2026
Other demons ran up to help force the meal down.
From "City of the Plague God" by Sarwat Chadda
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.
