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Synonyms

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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


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

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing paranoia

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.

"Paranoia - call it what you want - but definitely not criminal intent," he told the court.

From BBC • May 21, 2025

The scene had an eerie familiarity, Mohammed said, as if the horrors of the First and Second Intifadas, or Palestinian uprisings, were being replayed: Paranoia turning Palestinians against each other.

From Seattle Times • May 8, 2023

Paranoia, when you’re a parent, is everywhere, adds Wu, recalling how she Googled about sleep training when she had her baby — and got a hit about sudden infant death syndrome.

From Los Angeles Times • Nov. 16, 2022

Paranoia is found across historical time and space.

From Salon • Jul. 31, 2022

Paranoia was for Moon Girl, not for him.

From "Ship Breaker" by Paolo Bacigalupi