Definition of lethal in English:



  • 1Sufficient to cause death.

    ‘a lethal cocktail of drink and pills’
    • ‘The synthetically lethal combinations could not be analyzed because they did not grow under any conditions.’
    • ‘The offender appears to sleep peacefully before the lethal dose of poison is administered.’
    • ‘They're exposed every day to potentially lethal doses of anthrax.’
    • ‘Without the respectability that lethal injection provides, capital punishment in the United States would probably cease.’
    • ‘All four incidents involving the potentially lethal weapon happened within the space of an hour in Grimsby.’
    • ‘In the United States, critically injured racehorses are humanely euthanized by lethal injection.’
    • ‘Many dogs like the sweet smell and taste and, unfortunately, even very small amounts can be lethal to them.’
    • ‘The avian flu strain lethal to humans has so far killed 42 people in Vietnam since late 2003.’
    • ‘Actually, the mutation has proved lethal in a protected environment as well.’
    • ‘Who's to say that a substance lethal to rats would necessarily have the same effect on humans?’
    • ‘In fact, oxidative stress may progress to such an extent that it becomes lethal.’
    • ‘The gas acts like mustard gas, and can prove lethal to those with respiratory problems.’
    • ‘A deadly bird flu, lethal to some animals, is spreading towards Britain.’
    • ‘In sufficient quantities its spores can be lethal to humans.’
    • ‘Every car is a potentially lethal weapon of mass destruction.’
    • ‘The first, a yeast, can be especially lethal to individuals with weakened immune systems.’
    • ‘Although scorpion stings can be devastatingly painful, they are not usually lethal to humans.’
    • ‘Grey squirrels have out-competed reds for food and also carry squirrel-pox virus which is lethal to the native animals.’
    • ‘Antibiotics are medicines that are lethal to bacteria that cause infections.’
    • ‘Such a hostile chemical environment would likely prove lethal to all known microbes.’
    1. 1.1 Very harmful or destructive.
      ‘the Krakatoa eruption was the most lethal on record’
      • ‘Add to that an unhealthy dose of shame at her previous level of comfort, and you had a lethal combination.’
      • ‘That's a lethal combination when you're required to spend two hours with someone in a car.’
      • ‘Friday was a bizarre affair, fuelled by a lethal combination of beer, wine, Jack Daniels and vodka.’
      • ‘It's not just inactivity that makes excess TV-watching lethal to your waistline.’
      • ‘Are you prepared to consume that lethal dose of sodium and fat?’
      • ‘Entire governments, never mind single ministers, have been toppled by that lethal combination.’
      • ‘The lethal combination of peak hour traffic and rain had resulted in chaos on the roads.’
      • ‘Added to that is booze, which can make a lethal combination when added to football, causing fights and car accidents.’
      • ‘Too much time and money, little purpose, and boredom are a lethal combination.’
      • ‘In our schools, too, we should emphasize that it will be lethal to take the earth for granted.’
      • ‘The cider and vodka combination is far too lethal for my poor liver so I ended up puking.’
      fatal, deadly, mortal, causing death, death-dealing, life-threatening, murderous, homicidal, killing, terminal, final, incurable
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    2. 1.2 (in a sporting context) very accurate or skilful.
      ‘a lethal drop-shot’
      • ‘Despite scoring just nine goals in the league Manchester United possess potentially the most lethal striking quartet in the country.’
      • ‘With a lethal combination of range, strength and speed, Boston is a big play waiting to happen.’
      • ‘His connection with quarterback Jake Delhomme is almost telepathic, and his speed is lethal.’
      • ‘He has shown his lethal shooting touch but has yet to go on a tear, creating speculation he doesn't have much left.’
      • ‘Gooden is a tough cookie who can score, and Giricek is a lethal shooter who is underrated at being aggressive.’
      • ‘In the ring he is lethal, arguably the quickest fighter in history, with sneaky power and a flair for the dramatic.’
      • ‘The Real Madrid and former Inter striker whose credit includes sporting one of the worst haircuts in living memory is lethal in front of goal.’
      • ‘The diminutive striker displayed a lethal eye for goal for the Blues two seasons ago and was one of the top scorers in the Premiership.’
      • ‘Most other clubs can only drool at our rich vein of lethal finishers.’
      • ‘He can catch the ball in traffic as well as anyone in the league, and he's lethal after the catch.’
      • ‘Seven minutes before the break, however, Argentina once more showed how lethal they are when Riquelme is given time on the ball.’
      • ‘Rivaldo is equipped with a lethal left foot that has gone through more than a few defences.’
      • ‘Still only 19 years old, Ronaldo has gone from promising starlet to lethal player since the turn of the year.’
      • ‘The Bills' lethal vertical passing game will be tough to stop the rest of the season.’
      • ‘He is a true winger in the Ryan Giggs mould, hugging the touchline and whipping in crosses and lethal shots in great quantity.’
      • ‘Beautifully balanced and deceptively fast, he was a classic winger on the dribble, lethal on the turn inside the box.’
      • ‘Rush was one of the most lethal forwards of the past 25 years.’
      • ‘Maloney is a diminutive treasure, a pint-sized magician and, from free kicks, consistently lethal.’
      • ‘Sirotka doesn't blow hitters away with a big fastball, but he throws a lethal sinker and gets a lot of groundouts.’
      • ‘The striker was lethal with his finish, firing a beautiful curling shot that gave Williams no chance.’
      well aimed, precise, on target, unerring, deadly, sure, true, on the mark, careful, meticulous, painstaking, precision
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Late 16th century (in the sense ‘causing spiritual death’): from Latin lethalis, from lethum, a variant (influenced by Greek lēthē ‘forgetfulness’), of letum ‘death’.