paranoia

[par-uh-noi-uh] /ˌpær əˈnɔɪ ə/

noun

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.

baseless or excessive suspicion of the motives of others.

Also, paranoea

[par-uh-nee-uh] /ˌpær əˈni ə/ (Show IPA).

Origin

1805-15; < Neo-Latin < Greek paránoia madness. See para-, nous, -ia

Examples from the web for paranoia

But he insists that he doesn't seriously advocate total paranoia, just a little common sense.
His paranoia was in high gear.
Part of the downside of sustained use is paranoia and aggressiveness.
In a business where joke-stealing paranoia abounds, the camaraderie is unusual.
Nevertheless, a third of these volunteers felt significant fears afterward, and some experienced paranoia.
No need for paranoia, but many computer crimes are inside jobs.
The result was that once the tenure process was in its final swing, something like paranoia descended on whole departments.
Our paranoia over the word "radioactivity" continues to tie our hands again and again.
When this chilling shill paranoia sets in, you question your friends and you question yourself.
He was an isolated, unhappy man racked by bouts of paranoia.

British Dictionary definitions for paranoia

paranoia

/ˌpærəˈnɔɪə/

noun

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

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

(informal) intense fear or suspicion, esp when unfounded

Derived Forms

paranoiac (ˌpærəˈnɔɪɪk), paranoic (ˌpærəˈnəʊɪk) adjective, noun

Word Origin

C19: via New Latin from Greek: frenzy, from paranoos distraught, from para-1 + noos mind

Word Origin and History for paranoia

"mental disorder characterized by systematized delusions," 1848 (earlier paranoea 1811), from Greek paranoia "mental derangement, madness," from paranoos "mentally ill, insane," from para- "beside, beyond" (see para- (1)) + noos "mind."

FOR several years frequent descriptions have been given in the foreign journals, especially German and Italian, of the forms of insanity designated by the names Paranoia, Verrücktkeit, and Wahnsinn. ["Paranoia -- Systematized Delusions and Mental Degenerations," J. Séglas (transl. William Noyes), 1888]

paranoia in Medicine

paranoia par·a·noi·a (pār'ə-noi'ə)
n.

A psychotic disorder characterized by systematized delusions, especially of persecution or grandeur, in the absence of other personality disorders.
Extreme, irrational distrust of others.

paranoia in Culture

paranoia [(par-uh-noy-uh)]

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

Note: 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.