Definition of nebulous in English:



  • 1In the form of a cloud or haze; hazy.

    ‘a giant nebulous glow’
    • ‘It expanded into a nebulous circle of shifting light.’
    • ‘He nimbly steers his magic carpet through the nebulous and confusing post-modern clouds of the internet.’
    • ‘A thick, nebulous haze, caused by the manufacturing process, pervaded everywhere, revealing sparks and the blindingly bright radiance of welding from time to time.’
    • ‘Where others in this vein opt for a hazy, nebulous cloud of half-remembered dreams, Manitoba's music is direct and unassuming while still remaining evocative.’
    • ‘Smudges like this are called nebulae, because they look nebulous - like hazy clouds.’
    indistinct, indefinite, unclear, vague, hazy, cloudy, fuzzy, misty, lacking definition, blurred, blurry, out of focus, foggy, faint, shadowy, dim, obscure, shapeless, formless, unformed, amorphous
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    1. 1.1
      another term for nebular
      • ‘Shapley noted that nebulous objects tended to be everywhere except in the Milky Way plane.’
      • ‘Twenty five years ago, the nebulous gas entombing the dying star at the centre was not hot enough to glow.’
      • ‘The Pleiades is a nebulous cluster of stars, all contained within one degree of longitude, located on the shoulder of the Bull.’
      • ‘It has few distinguishable stars and is mainly notable for a nebulous, cloud-like cluster which ancient astronomers regarded as an area where energies were dissipated.’
      • ‘The billions of years believed necessary for the earth to evolve from some nebulous mass simply evaporate when confronted by such evidence.’
  • 2(of a concept) vague or ill-defined.

    ‘nebulous concepts like quality of life’
    • ‘But can I ask you - and this is a bit of a nebulous question I suppose - but what do you think of when the term ‘respect’ comes up?’
    • ‘For nebulous, ambiguous speculation, nothing comes close to this work.’
    • ‘The focus is on ‘experience’, which is a bit nebulous in comparison to a conference on technology or design, but that's what makes it fun and interesting.’
    • ‘That's the reassurance I want, not this nebulous approach.’
    • ‘He did not peer through a hazy lens into a nebulous future.’
    • ‘Yet there are dinosaurs who take a dim view of such a plan, their highly specious argument revolving around the nebulous concept of loyalty.’
    • ‘At the end of the day, after two hours of ‘debate’, it emerged that what people wanted was that nebulous old chestnut, ‘freedom of choice’.’
    • ‘Yet dark energy is a nebulous concept, one that has thus far flummoxed some of the smartest researchers on the planet.’
    • ‘He is adamant that this week he wants us to take immediate actions and clearly report what we see and do, rather than just speculate and make nebulous plans for the future.’
    • ‘That's a much more nebulous and difficult question.’
    • ‘Rock ‘n’ roll, however, is a most nebulous phenomenon.’
    • ‘Ultimately, it's not politics that makes the world go round but generosity, but for a lot of people that's a very nebulous concept.’
    • ‘No doubt there'll be some spurious, nebulous rhetoric about rights and responsibilities, respect, choice and other such middle class emollients.’
    • ‘Discretion is a nebulous thing, each case is different and what we are saying is that the HSE doesn't appear to look at cases individually.’
    • ‘Nowadays they want something far more nebulous, which is celebrity.’
    • ‘Goals have to be defined and solid, otherwise they are nebulous - like clouds.’
    • ‘Having spent many years ‘dabbling in the history of ideas,’ we are well aware that the term ‘postmodern’ is a nebulous concept.’
    • ‘This is the first in a series that explores the nebulous connection between modern art and cartooning.’
    • ‘Instead, they invented this nebulous concept of the ‘public domain’ that no one owns.’
    • ‘Of course, this risks the subordination of personal freedom to some nebulous concept of public good.’
    • ‘Most irritating of all, I'm finding that my brain is absolutely unable to cope with vague, nebulous concepts or ideas.’
    • ‘Why do you think scientists have been reluctant to grapple with this nebulous notion of the human mind?’
    vague, ill-defined, unclear, hazy, uncertain, indefinite, indeterminate, imprecise, unformed, muddled, confused, ambiguous, inchoate, opaque, muddy
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Late Middle English (in the sense ‘cloudy’): from French nébuleux or Latin nebulosus, from nebula mist. nebulous dates from the early 19th century.