Definition of delusion in English:



  • 1An idiosyncratic belief or impression maintained despite being contradicted by reality or rational argument, typically as a symptom of mental disorder.

    ‘the delusion of being watched’
    • ‘He has grandiose delusions and does not want to stay in hospital.’
    • ‘Psychotic patients may have paranoid delusions about their food, leading to reduced intake.’
    • ‘In the paranoid form of this disorder, they develop delusions of persecution or personal grandeur.’
    • ‘Is this for real, or just a delusion on my part?’
    • ‘Such a grandiose delusion is common to the consideration of an insanity defense.’
    • ‘He was a realistic man who harbored no delusions about immortality.’
    • ‘The rise of psychoanalysis did much to validate the contents of mental symptoms, including delusions.’
    • ‘Psychotic delusions, say of being invincible, are a common element of mania.’
    • ‘What did they call it when two people shared a delusion?’
    • ‘Narcissism is a noxious mental disease that leads people to grandiose delusions.’
    • ‘The doctors had been aware that he harboured violent delusions.’
    • ‘I think I mentioned somewhere that delusions are visions of realities not yet activated.’
    • ‘LSD can induce a psychotic state with paranoid delusions that can last for months.’
    • ‘In other words, this was another sensational example of what sociologists call collective delusions.’
    • ‘No talk show host or publisher invited them to share their delusions with the world.’
    • ‘Is it all a mass delusion, or is there something to it all.’
    • ‘In some non-Western cultures, schizophrenic delusions single out the person as spiritually gifted.’
    • ‘Schizophrenia, a biological disorder of the brain, is characterised by delusions, hallucinations and thought disorders.’
    • ‘Many are filled with hate and delusions of superiority; some are actually psychotic.’
    misapprehension, mistaken impression, false impression, mistaken belief, misconception, misunderstanding, mistake, error, misinterpretation, misconstruction, misbelief
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    1. 1.1[mass noun]The action of deluding or the state of being deluded.
      ‘what a capacity television has for delusion’
      • ‘The rest of us play along, but no one is fooled by this necessary delusion.’
      • ‘What is deceit or delusion, and what is genuine in this movement?’
      • ‘It took me 15 years to realise that it was a tragic, sickly delusion.’
      • ‘In short, the evidence points more towards hoaxing and delusion than real discovery.’
      • ‘This is one of the first steps he takes towards differentiating between delusion and fact.’
      • ‘The collapse of idea in Europe may yet be the event that will snap Britain awake from a 30-year delusion.’
      • ‘Now mass delusion is not necessarily a bad thing.’
      • ‘So many of us live in a life of delusion, of separation, of selfishness and of loneliness.’
      deception, misleading, deluding, fooling, tricking, trickery, duping
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Late Middle English (in the sense ‘act of deluding or of being deluded’): from late Latin delusio(n-), from the verb deludere (see delude).