paranoia

American  

[par-uh-noi-uh] / ˌpær əˈnɔɪ ə /

Archaic, paranoea

noun

1. Psychiatry. a mental disorder characterized by systematized delusions and the projection of personal conflicts, which are ascribed to the supposed hostility of others, sometimes progressing to disturbances of consciousness and aggressive acts believed to be performed in self-defense or as a mission.

2. baseless or excessive suspicion of the motives of others.

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paranoia British  

/ ˌpærəˈnɔɪɪk, ˌpærəˈnəʊɪk, ˌpærəˈnɔɪə /

noun

1. a form of schizophrenia characterized by a slowly progressive deterioration of the personality, involving delusions and often hallucinations

2. a mental disorder characterized by any of several types of delusions, in which the personality otherwise remains relatively intact

3. informal intense fear or suspicion, esp when unfounded

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paranoia Cultural  

1. A form of psychosis marked by delusions of persecution and of grandeur. One who suffers from paranoia is paranoid.

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Usage

What does paranoia mean? Paranoia is a mental disorder characterized by delusions and feelings of extreme distrust, suspicion, and being targeted by others. Paranoia is also commonly used more generally to mean extreme suspicion or irrational distrust of others. It’s important to understand that while paranoia is used generally outside of its psychiatric usage in a way that makes it seem less serious, having paranoia is a major symptom of disorders like paranoid schizophrenia and paranoid personality disorder. The adjective paranoid can be used to describe a person, action, or thought that exhibits paranoia. A rare alternate spelling for the word is paranoea. Example: Locking my doors at night isn’t a sign of paranoia—it just means I’m being cautious.

Discover More

In popular terminology, a “paranoid” personality is characterized by suspicion and distrust of others; a tendency to look for hidden meaning behind other people's actions; argumentativeness; complaining; low tolerance for criticism; and a constant display of one's own talents, accomplishments, independence, and rationality.

Other Word Forms

• paranoiac
  adjective

Etymology

Origin of paranoia

First recorded in 1805–15; from New Latin, from Greek paránoia “madness,” from paráno(os) “demented” (equivalent to para- ¹ + nous ) + -ia -ia

Explanation

Something that happens to a person's thinking can lead to paranoia. You may believe that your friends no longer like you, but it's just that your paranoia makes you suspicious of everyone. Paranoia is from the Greek para-, "beyond, irregular," and noos, "mind." It is an irregularity of the mind, a mental disorder that distorts a person's perception of what is real. Someone with paranoia may believe that other people are out to get them or are watching them all the time. Doctors who treat paranoia look for causes, and while patients can develop the disorder gradually and sometimes due to life circumstances, such as abuse or neglect, the use and abuse of drugs can also cause paranoia.

Example Sentences

The result in Beijing verged at times towards collective paranoia.

From Barron's • May 15, 2026

“His decisions at trial,” his lawyers argue, were “based on fear and paranoia rather than rational thinking; he would fixate on small details, while missing the big picture.”

From Slate • Apr. 20, 2026

As the obstacles mount against Kornev, his paranoia grows, leading to fleeting moments of surrealism.

From Los Angeles Times • Mar. 26, 2026

In a sign of his deep paranoia, he told Fox News in 2025 he is so afraid of being carjacked that he doesn’t wear a seatbelt, even though carjacking rates are rapidly falling.

From Salon • Mar. 18, 2026

Yet Szilard had learned from bitter experience that sometimes paranoia is the prudent approach.

From "Big Science" by Michael Hiltzik

Related Words

• insanity
• mental disorder