demon

B2 · Upper Intermediate Countable noun

n. a strong, painful feeling or a bad habit that is hard to control.

n. a source of persistent psychological torment, distress, or a destructive personal habit.

“The retired athlete struggled with his own demons after his career ended.”

“The biography explores how the artist battled his inner demons through his work, often painting late into the night to escape his anxiety.”

C1 · Advanced Countable noun Informal

n. someone who does something with a lot of energy, speed, or skill.

n. a person who performs a particular activity with great enthusiasm, energy, or technical proficiency.

“She is a demon on the tennis court and rarely loses a match.”

“Known as a demon for detail, the editor spent weeks ensuring every citation in the manuscript was perfectly formatted.”

C1 · Advanced Countable noun Computing Technical

n. a background program on a computer that handles specific tasks without the user seeing it.

n. a background process that handles system tasks or requests without direct user intervention; often spelled 'daemon'.

“The print demon handles all the documents you send to the printer.”

“The system administrator noticed that a rogue demon was consuming excessive CPU cycles, slowing down the entire server network.”

C2 · Proficiency Countable noun Science Technical

n. an imaginary creature used in science to explain how energy and heat work.

n. a hypothetical being used in thought experiments to illustrate physical laws, most notably Maxwell's demon.

“Maxwell's demon is a famous idea used to talk about the laws of physics.”

“The professor used the concept of Maxwell's demon to challenge the students' understanding of the second law of thermodynamics.”