Definition of combustible in US English:



  • 1Able to catch fire and burn easily.

    ‘highly combustible paint thinner’
    • ‘When exposed to a fire, the chemicals react with the combustible gasses normally produced by untreated wood as it burns, converting them to carbon char, carbon dioxide and water.’
    • ‘It was fired by lighting a combustible cartridge.’
    • ‘It is combustible like everything else in this room.’
    • ‘But don't worry - you won't be receiving anything spontaneously combustible or explosive.’
    • ‘If the materials are combustible, the fire protection system will be designed differently than for a noncombustible building.’
    • ‘Fire can do nothing but burn, but it does burn if there is something combustible, if this fuel is close enough to the fire, and if nobody throws water on.’
    • ‘Should a fire strike, the chemicals react with combustible gases and tars normally generated by the material.’
    • ‘She is unhappy that the paintings were stored on an industrial estate alongside combustible gas canisters, and that there was no security guard employed.’
    • ‘He also devised portable hydrogen-gas generators that combined sulfuric acid and iron shavings to produce combustible gas.’
    • ‘A fire brigade spokesman said that a high density of flammable gas released by combustible shoemaking materials and poor ventilation in the workshop probably was to blame for the blaze.’
    • ‘Bonfires are a big part of Hallowe'en and often contain highly combustible materials that can cause respiratory problems and burns.’
    • ‘In other words, oil does not burn because it has combustible properties.’
    • ‘The ministry circulated a press release - shunning the hesitation and obscurity that usually takes it a lot longer to respond - saying the man was hurt in an explosion generated by combustible trash he kept in his house.’
    • ‘Nearly 60 per cent of candle fires start when the flame comes into contact with nearby combustible materials.’
    • ‘They fear possible gas leaks and fires being started by combustible materials deposited in the huge caves created by mining activities.’
    • ‘It was jamming up a ventilation grate, blocking up the flow of combustible gas below it.’
    • ‘Keep combustible liquids such as paint thinner, kerosene, charcoal lighter fluid, and turpentine away from heat sources.’
    • ‘There were still 300 tons of combustible materials and there have been frequent fires giving off fumes that affect local residents and people working nearby.’
    • ‘A spokesman from Wiltshire Fire Brigade warned that this time of year is dangerous for countryside fires because of the dry conditions and amount of combustible material around.’
    • ‘Cleaning means removing the hazard of accumulated and highly combustible creosote produced by burning wood and wood products.’
    inflammable, flammable, incendiary, explosive
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    1. 1.1 Excitable; easily annoyed.
      ‘two combustible personalities’
      • ‘They may not quite have the combustible mix of personalities of the two great Americans.’
      • ‘His combustible persona waxed hot against those he saw as enemies of righteousness and justice, attracting true believers to its incandescence.’
      • ‘Prior to his conversion, the part-time manicurist had a reputation for hard partying and a combustible personality.’
      • ‘The result is not only more subdued than one might expect of the combustible personalities at work here, but also more intelligent, more intellectual, even, and more profound.’
      • ‘In a society seeking moral footing after 50 years of totalitarian rot, he found these public manners personally appalling and potentially combustible.’


  • A combustible substance.

    • ‘‘The way it was contained in a hallway, which normally would have no combustibles in it at all, makes it highly suspicious,’ he said.’
    • ‘Several involve body-shaped depressions in the earth that are filled with fabric or other combustibles, set afire and left as an imprint of ash.’
    • ‘‘We say as a rule of thumb keep all combustibles a metre from the heater,’ Chris said.’
    • ‘Enough heat can also conduct through a perfectly sound chimney to ignite nearby combustibles.’
    • ‘Who will be the first to locate York's secret stash of combustibles?’
    • ‘As mentioned earlier, the only childhood task I dreaded more than fetching things was hauling combustibles, like paper, down to the shacks by the creek.’
    • ‘Ideally, thatch roofing and other combustibles were removed.’
    • ‘Keep furnaces and gas water heaters clear of piled-up boxes or any other combustibles.’
    • ‘Primarily under the guise of electricity or combustibles, energy is hardly given a second thought.’
    • ‘The practise is a success when the right combustibles meet the right materials.’
    • ‘Pegged rate systems are great for fueling crises, like oily combustibles lying around in a garage; a small flame can start a great fire and take down a house.’
    • ‘I had a look at the company's website and they were storing a veritable cornucopia of combustibles in that place including naptha, a substance used in dry cleaning.’
    • ‘Class A extinguishers are used for ordinary combustibles including wood and paper.’
    • ‘The fire service advises keeping candles away from decorations and other combustibles and warn alcohol can increase the chance of making a mistake, so think twice before doing anything that can cause a fire.’
    • ‘For units that use inside air for combustion, be sure to provide ample clearance so that nearby air can flow easily, and make sure that everyone in the family knows not to put combustibles nearby.’
    • ‘Always clear the area below cutting or welding operations so hot slag will not drop on hoses, cables, flammables, combustibles or employees.’
    • ‘At the far end of the walkway, on the very spot where he had held his bonfires of the vanities, stood a circular wooden platform, heaped with combustibles.’
    • ‘Class A Extinguishers can be used on ordinary combustibles such as wood, cloth, and paper.’
    • ‘Fearing for the safety of nearby combustibles, I whipped the pan off the stove (blistering my thumb in the process) and was overwhelmed with thunderous applause.’
    • ‘As the mortar joints erode, heat transfers more rapidly to the nearby combustibles and dangerous gases such as carbon monoxide can leak into the living areas of the home.’
    power source, heat source, combustible, propellant
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Early 16th century: from Old French, from late Latin combustibilis, from Latin combust- ‘burnt up’, from the verb comburere.