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paranoid

[par-uh-noid]
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adjective
  1. of, like, or suffering from paranoia.
noun
  1. a person suffering from paranoia.
Also par·a·noi·ac [par-uh-noi-ak, -ik] /ˌpær əˈnɔɪ æk, -ɪk/, par·a·noe·ac [par-uh-nee-ak, -ik] /ˌpær əˈni æk, -ɪk/.

Origin of paranoid

1900–05; paranoi(a) + -oid, with base and suffix merged, perhaps by haplology from the expected *paranoioid
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for paranoiac

Historical Examples

  • And the forty millions still alive were restless, frightened, paranoiac.

    It's All Yours

    Sam Merwin

  • To use a philosophical term, the paranoiac is the Simon-pure "solipsist."

    The Behavior of Crowds

    Everett Dean Martin

  • It is precisely what the paranoiac does after his own fashion.

    The Behavior of Crowds

    Everett Dean Martin

  • It clings to its fixed ideas with the same tenacity as does the paranoiac.

    The Behavior of Crowds

    Everett Dean Martin

  • His delusions became systematised with all the ingenuity of the paranoiac.

    Modernities

    Horace Barnett Samuel


British Dictionary definitions for paranoiac

paranoid

adjective
  1. of, characterized by, or resembling paranoia
  2. informal exhibiting undue suspicion, fear of persecution, etc
noun
  1. a person who shows the behaviour patterns associated with paranoia
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

Word Origin and History for paranoiac

1892 (n. and adj.), from paranoia on model of maniac, etc.

paranoid

adj.

1901, irregularly formed from paranoia + -oid. As a noun, "a paranoid person," attested from 1922.

Online Etymology Dictionary, © 2010 Douglas Harper

paranoiac in Medicine

paranoiac

(păr′ə-noiăk′, -noiĭk)
n.
  1. A paranoid.
adj.
  1. Of, relating to, or resembling paranoia.

paranoid

(părə-noid′)
adj.
  1. Relating to, characteristic of, or affected with paranoia.
n.
  1. One affected with paranoia.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.