Definition of lunatic in English:



  • 1A person who is mentally ill (not in technical use).

    • ‘Consequently, I babbled like a deranged lunatic, and it wasn't pretty.’
    • ‘Surely many people who try to attempt suicide are emotionally not entirely unstable - yet they're generally not fools or lunatics.’
    • ‘Everyone you know here is now either dead, a psychopathic killer out for blood, or a lunatic with about a hundred personalities.’
    • ‘Individuals with severe mental illnesses, branded as ‘non-criminal lunatics,’ are often imprisoned.’
    • ‘She continued to gape at him as if he was a runaway lunatic from a nearby mental asylum.’
    • ‘If he had been psychotic before, he was a fuming lunatic now, Evelyn decided.’
    • ‘In the darkness, a lunatic warbled nonsense and a hungry madman babbled on about food.’
    • ‘The gaol was also used for a number of years to house the mentally insane, as lunatics had to be restrained and kept out of sight.’
    • ‘To many people, these beliefs sound like the delusions of lunatics and it seems inconceivable that anyone in his or her right mind would accept such beliefs.’
    • ‘Though I have some mental health issues, I am not a raving lunatic.’
    • ‘Initially, he's told he's too old and then parcelled off into the Halberdiers, a regiment almost entirely comprised of oddballs, lunatics, misfits and sociopaths.’
    • ‘I didn't shower for at least 3 days and roamed the drugstore aisles like a crazed lunatic.’
    • ‘Who knew what kind of psychopathic lunatics crept around there?’
    • ‘Countless lunatics, criminals, and other undesirables were photographed in the genuine belief that the results would aid science.’
    • ‘She watched, with her mouth wide open, for about ten second before taking a deep breath, and letting out a string of curses, loud enough for random passers-by to think she was an insane lunatic.’
    • ‘My guess is that he's either a known criminal or an escaped lunatic.’
    • ‘By saying that I am in no way implying that he was a crazed lunatic.’
    • ‘‘Probaly some lunatic escaped from a mental hospital,’ Diana suggested, the color slowly seeping back into her face.’
    • ‘There he encounters a lunatic who is obsessed with murder and who appears to be dripping blood.’
    • ‘On the right is the first victim, the lunatic who had lived his last moments in fear of death, and had sadly found it after seeking refuge in my asylum.’
    maniac, madman, madwoman, psychopath, psychotic
    mad, insane, mentally ill, certifiable, deranged, demented, of unsound mind, out of one's mind, not in one's right mind, sick in the head, not together, crazy, crazed, non compos mentis, unbalanced, unhinged, unstable, disturbed, distracted, stark mad, manic, frenzied, raving, distraught, frantic, hysterical, delirious, psychotic, psychopathic, mad as a hatter, mad as a march hare, away with the fairies, foaming at the mouth
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    1. 1.1 An extremely foolish or eccentric person.
      ‘this lunatic just accelerated out from the side of the road’
      • ‘When you see a picture of some mud-spattered lunatic on a 4,000 mile ride through Africa, the lunatic tends to be sitting on a BMW.’
      • ‘He has observed that all the other drivers on the road fall into one of two categories: idiots or lunatics.’
      • ‘And by the looks of it, this was one of those lunatics.’
      • ‘Technically, the old lunatic hadn't retired, he was just on stress leave.’
      • ‘And then there are the rest of the lunatics who sign up.’
      • ‘He doesn't deserve threats and abuse along these lines from a bunch of lunatics denouncing our democratic process.’
      • ‘Although we may tend to laugh at the flagellants and read them off as lunatics, they did help medieval men and women cope with the ravages of the plague.’
      • ‘Those of you who are not my best friend Julie, and therefore not lunatics and hardcore math geeks, may not know that today is Pi Day.’
      • ‘As the playboy freshly back from the U.S. keeps repeating, ‘This is a city of lunatics!’’
      • ‘Back in the 1970s, its supporters were considered kooks and lunatics.’
      • ‘He had known it, the rest of his friends were raving lunatics.’
      • ‘I really enjoy hearing from you all (even the complete lunatics).’
      fool, idiot, imbecile, moron
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  • 1Mentally ill (not in technical use)

    ‘a ward of lunatic old ladies’
    • ‘In the rare cases of lunatic parents most places have emancipation provisions already, which should surely have acceleration clauses to allow for quick decisions in cases like this.’
    • ‘The frustration is so great that the black character believes that he might wind up in a lunatic cell, driven crazy by the insane demands.’
    • ‘These are not the ravings of a lunatic person nor the dream of a crazy idealist.’
    • ‘Do you remember that one episode of X-Files with that crazed lunatic writer who was in love with Scully?’
    • ‘I said I found him, not that he was some insane lunatic murderer trying to kill me!’
    deranged, demented, unbalanced, out of one's mind, crazed, mad, insane
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    1. 1.1 Extremely foolish or eccentric.
      ‘he would be asked to acquiesce in some lunatic scheme’
      • ‘They will presumably lead to some retraction of the lunatic version of markets that have been imposed by extreme reactionaries in recent years.’
      • ‘There is, blatantly, far too much pampering these days of egos founded not on a record of achievement but on the bloated salaries considered normal amid the lunatic values that have invaded the national sport.’
      • ‘At first, two or three miles may seem well nigh impossible - but eventually such a distance will become easy, and so it goes until running, say, ten miles is no longer a lunatic notion.’
      • ‘The United Nations and NASA insist no one can own any part of the moon, but interplanetary auctioneers are selling parts of it at a lunatic price of £10 per acre.’
      • ‘This is a hateful thought for greenies, social engineers, media elites and intellectuals everywhere, but the lunatic love affair with the car remains in a state of steamy passion.’
      • ‘When everything that's going on on-screen is so chaotic and crazy, it doesn't help when it's cut together with such lunatic randomness.’
      • ‘What sort of lunatic performer was this, driven to go on performing the same stunt, time after time, finally without any audience at all, entirely for his own pleasure?’
      • ‘There have been many other dissenting voices protesting the sale of public sector companies but these have been largely disregarded as the predictable ravings of the lunatic Left.’
      • ‘Lincolnshire roads tend to be populated with lunatic drivers on a Saturday evening, all hurrying to get there first and competing to see who'll be added to the casualty figures for the weekend.’
      • ‘Cutting a path through the thickets of misrepresentation, misunderstanding and lunatic theorising that have grown up around the symbol of the Grail is no easy task.’
      • ‘It's all there - the hatred, the bitterness, the lunatic conspiracy theories, the utter absence of any substantive discussion of policy issues.’
      • ‘Some of this is emanating from the usual sources on the lunatic left of journalism, but the allegations are retailed generally by those who want to believe them, under the guise of merely reporting disquiet.’
      • ‘I am particularly intrigued by the prospect of working for another lunatic director with no interpersonal skills, management ability, or capacity for leadership.’
      • ‘I shook my head and locked myself in the bathroom to take a shower, hoping my crazy, lunatic uncle would let us out before then.’
      • ‘The silent threat of violence hangs in the air and a bunch of lunatic architects were let loose with gallons of concrete in the 60's and 70's.’
      • ‘What happens if you break all the rules and throw your reputation behind a lunatic scheme to let people hear world-class classical music for the price of a couple of pints?’
      • ‘‘We have arrived at a lunatic situation where there is one law for one group and a different law for others,’ he said.’
      • ‘A small smile touched her lips, her eyes alight with a lunatic fire.’
      foolish, silly, unintelligent, idiotic, brainless, mindless, scatterbrained, crackbrained, nonsensical, senseless, irresponsible, unthinking, ill-advised, ill-considered, inept, witless, damfool, unwise, injudicious, indiscreet, short-sighted
      foolish, stupid, silly, idiotic, half-witted, witless, brainless, mindless, thoughtless, imprudent, incautious, irresponsible, injudicious, indiscreet, unwise, unintelligent, unreasonable
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Middle English: from Old French lunatique, from late Latin lunaticus, from Latin luna ‘moon’ (from the belief that changes of the moon caused intermittent insanity).