Definition of deadly in English:



  • 1Causing or able to cause death.

    ‘a deadly weapon’
    • ‘It feels as if only the ultimate extinction of the human race will able to stop that deadly spiral.’
    • ‘It is also important to remember that every driver on the highway is armed with a weapon more deadly and dangerous than any firearm: a motor vehicle.’
    • ‘The gas was refined and is less toxic but still toxic enough to be deadly to humans over time.’
    • ‘The director of Amnesty International UK has appealed to the people of west Wiltshire to support the charity's campaign against the worldwide trade in deadly weapons.’
    • ‘In Doomsday Book the twenty-first century is stricken by yet another pandemic, almost as deadly as the Black Death was in the fourteenth.’
    • ‘Greed is their most deadly sin, because none of them can escape it.’
    • ‘Now the fire itself wasn't very deadly, it was the smoke.’
    • ‘And in doing so there's a distinct possibility that deadly force will have to be used.’
    • ‘He faces charges of assault with a deadly weapon.’
    • ‘Tobacco is ' one of the most deadly poisons'.’
    • ‘Big SUVs and little kids, a dangerous and sometimes deadly combination in the family driveway.’
    • ‘The aftershock is equally deadly for those who live in the vicinity.’
    • ‘Scientists hope new research could result in a vaccine for the potentially deadly meningitis B virus.’
    • ‘But in the latest two-week period, seven chickens tested positive for the potentially deadly virus.’
    • ‘The 2003 death toll from the deadly virus was only one.’
    • ‘New intelligence indicates explosives set off to the side of the road are proving very deadly.’
    • ‘Asthma is at best an annoying condition, and at worst a debilitating, even deadly disease.’
    • ‘They help to prevent more deadly diseases from affecting your pet.’
    • ‘British leaders say the mistaken shooting last Friday was a tragedy, but they insist police must be able to use deadly force to protect the public.’
    • ‘Agent Orange contained dioxins, which are some of the most deadly poisons known.’
    fatal, lethal, mortal, death-dealing, life-threatening
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    1. 1.1Filled with hatred or intense rivalry.
      ‘we are deadly enemies’
      ‘his voice was cold and deadly’
      • ‘Barth said without thinking, looking wretchedly into the beautiful deadly face, hating her for smiling, and not being the empress.’
      • ‘His voice was deadly and calm as he walked toward them.’
      • ‘Whipping around her skirt, it pulled her auburn hair away from her face, somehow making her look beautiful and deadly all in one moment.’
      • ‘Some were related; some were colleagues and friends; others were deadly enemies.’
      • ‘His eyes filled with cold, deadly venom, and a short snarl escaped his lips.’
      • ‘Their hate campaign is paying deadly dividends.’
      • ‘An unearthly calm seemed to come over him then, and there was a feeling of deadly malice, of hate and violence radiating from him that made her flinch from his stare.’
      • ‘Voice hated Azrael with a deadly passion.’
      • ‘"You killed her, " Amy said her voice deadly and unforgiving.’
      • ‘They are murderous, they are frustrated and they are deadly.’
      • ‘The greatest tragedy of the overseas democratic movement is that your ‘own people’ are often your most deadly enemy.’
      • ‘Tommy glanced at her face in complete shock and finally received an expression, a deadly one.’
      • ‘The two men, who were once close allies but are now deadly enemies, are sharing the same hotel in Seoul.’
      • ‘Grant projects a steady threat of violence, as though he could go over the edge from debonair to deadly at any moment.’
      • ‘The nation is at war against deadly enemies.’
      • ‘Her tone was flat and deadly, her fingers curled stiffly into something like claws.’
      mortal, irreconcilable, implacable, remorseless, relentless, unrelenting, unappeasable, unforgiving, merciless, pitiless
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    2. 1.2(typically in the context of shooting or sports) extremely accurate, effective, or skillful.
      ‘his aim is deadly’
      • ‘He throws the ball straight with deadly accuracy.’
      • ‘Hinting at the timepiece's capacity for deadly accuracy, he adds: ‘It was twenty-four minutes past midnight.’’
      • ‘He charges like a mad man, swinging wildly yet very deadly and quite accurate.’
      • ‘The one warrior, though not being nearly as powerful as the other, was quite quick and her fighting style deadly.’
      • ‘Taking aim she hurled her daggers at her enemy with deadly precision.’
      • ‘A flat free-kick of typically deadly pace from David Beckham brushed the head of the Paraguay captain Carlos Gamarra and continued on its path to the net.’
      • ‘Practice this in front of a mirror until you can slightly part your lips and silently hit a target with deadly accuracy.’
      • ‘Kendal's third and fourth goals also came from penalty corners again from Brooks, who dispatched accurately positioned balls with deadly accuracy.’
      • ‘You rely on body armor, luck, and your deadly accuracy to survive.’
      • ‘Each strike and block was performed with flawless, deadly accuracy.’
      • ‘There's something scary about a spare ball that can look this good and be so deadly.’
      • ‘Tyger threw the ball with deadly accuracy right at the monster's chest.’
      • ‘Not an International, but proving deadly in the Premiership whilst his form lasts.’
      • ‘And because I came from a single-income family, I was eligible for a student allowance, even with the deadly radar of means-testing.’
      • ‘He is hilarious when he plays a woman, because he nails it with deadly accuracy.’
      unerring, unfailing, impeccable, perfect, flawless, faultless, assured, sure, true, precise, accurate, correct, exact, direct, on target, on the mark
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    3. 1.3informal Extremely boring.
      ‘he's well meaning, but so utterly deadly’
      • ‘Viewers today typically consider busts academic, boring, deadly; in a museum, they are what you walk past on the way to the Impressionists.’
      • ‘Quiet filled the long, deadly moments that Abigail and James Corinne spent simply gawking at Callie.’
      • ‘I barely even notice the battle anymore through the deadly monotony.’
      • ‘Bemused glances helped them get through that deadly sermon.’
      • ‘As a result, cultural choice is increasingly restricted, and a bland sameness, deadly and soporific, threatens the cultural landscape.’
      • ‘"I only joined because of my mother," Chris tells her friend Annie after they've snickered through another deadly lecture on broccoli or carpet.’
    4. 1.4[attributive]Complete; total.
      ‘she was in deadly earnest’
      • ‘After a moment of deadly silence, the general spoke.’
      • ‘This is a continuous blast, until the eye of the hurricane reaches you and you get half and hour or so of deadly quietness.’
      • ‘Morgan Freeman was now speaking in deadly earnest about Rainforests as the Lungs of Our Planet.’
      • ‘Let us take this issue with the deadly seriousness that it deserves -- not only on this International Day, but every day.’
      • ‘There are things of deadly earnest that can only be mentioned under the cover of a joke.’
      • ‘Byron may have been playing at soldiers, but at the same time he was in deadly earnest.’
      • ‘There was a moment of deadly calm before people began to move, soft moans of pain from all around.’
      completely, absolutely, totally, utterly, perfectly, entirely, wholly, fully, quite, dead, thoroughly
      in every way, in every respect, in all respects, one hundred per cent, every inch, to the hilt, to the core
      intense, great, marked, extreme, excessive, immoderate, inordinate
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  • 1[as submodifier] In a way resembling or suggesting death; as if dead.

    ‘her skin was deadly pale’
    • ‘I lay deadly still and tried to listen for a sound to give me a clue to where I was, but all I could hear was my own erratic breathing.’
    • ‘All the while being deadly silent, since I live with my grandmother and her bedroom is right next to the bathroom.’
    • ‘The party mood was gone and everyone was deadly quiet.’
    • ‘His face was deadly white, a bloody bandage swathed his neck, and his rainproof was soaked with the blood of a sniper's victim.’
    deathly, deathlike, ashen, ghostly, white, pallid, wan, pale, ghastly
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    1. 1.1Extremely.
      ‘a deadly serious remark’
      • ‘The system at Dachau was simple, but deadly effective.’
      • ‘She should still feign indifference in the entire matter, no matter how deadly curious she was.’
      • ‘It is a deadly dull subject, almost guaranteed to drive away both voters and readers.’
      • ‘"Let me tell you something, " Christian continued, his voice deadly soft.’
      • ‘Heart failure is a deadly serious condition, but with good treatments people can double or triple their life expectancy.’
      • ‘‘I had the chance to sell to Honda, but I was deadly determined to do it on my own at that stage and that was '97,’ he said.’
      • ‘It's been a long and busy day, and the weather has been deadly dull and grey.’
      • ‘But there are other worthy contenders too - deadly fast men such as Holding and Walsh, and artful slow bowlers like Ramadhin and Gibbs.’
      • ‘This is not something I've ever done and I'm deadly uncomfortable with conflict, always have been, so this is quite a stretch.’
      • ‘On the one hand, a nightmarish reality; on the other, a deadly boring dream.’
      • ‘Elves are that way though, jolly one moment and deadly serious when the situation needs it.’
      • ‘I mean, even the last book I read was so deadly dull I had to skim the last third just to get it over with.’
      • ‘It is journalistic slop, political flatulence and religious aggrandisement, and it is deadly dangerous.’
      • ‘Not even that deadly cute Lulu Guinness I saw at Nordie's.’
      • ‘Every inch the deadly precise aristocrat, Harris shines brighter than any other star in Enemy at the Gates.’
      • ‘They are a deadly efficient machine, especially locally.’
      • ‘This joking remark caused Eisenhower to turn deadly serious.’
      • ‘In particular, the host, Killian, feels that he would be the perfect contestant on the deadly popular show.’
      • ‘The Gunners had the most disastrous of starts, conceding a goal to the deadly dangerous John O'Brien inside a minute and going four points behind with just ninety seconds on the clock.’
      • ‘Bing Crosby was deadly afraid of heights.’


Old English dēadlīc mortal, in danger of death (see dead, -ly).