Definition of thirty in English:


cardinal number

  • 1The number equivalent to the product of three and ten; ten less than forty; 30.

    ‘thirty or forty years ago’
    ‘thirty were hurt’
    ‘thirty of her school friends’
    • ‘Most of the political philosophy written in the last thirty years has been on this question.’
    • ‘More people were killed in political violence in those four years, than in the previous thirty.’
    • ‘He is apt to spend thirty or forty pages on an incident to which an equally good writer might devote three.’
    • ‘All thirty of them huddled by the fire, hoping to be shielded from the wicked wind.’
    • ‘It has rained and blown a gale continuously now for over thirty hours!’
    • ‘After a good thirty yards she came to a heavy wooden door that was locked.’
    • ‘He had put himself on a fixed budget and couldn't afford to spend more then thirty to forty dollars a day.’
    • ‘There were thirty or forty people there, which was an excellent turnout.’
    • ‘We stood, awkwardly for a full thirty seconds, before he seemed to jolt back to life.’
    • ‘But there is no doubt in my mind that people were happier thirty or forty years ago.’
    • ‘Typical notice periods are thirty, sixty and ninety days, although some are as short as seven days.’
    • ‘She normally makes thirty forty different scans from a set of flowers, before she finds an image that interests her.’
    • ‘These policies established the main outlines of British policy over the following thirty years.’
    • ‘On checking my bank statement last Friday, I discovered that I had a mere thirty pence to last me until payday at the end of July!’
    • ‘About thirty or forty were injured, including more than a dozen elderly persons.’
    • ‘The only recourse is for Ed to drive thirty miles to the nearest hospital for help.’
    • ‘However, there is a thirty percent decrease in fluorescence intensity of the polymer.’
    • ‘There were four tents in all, three for the thirty male soldiers and one for the ten females.’
    • ‘He had no devoted readership and little chance of remaining in print for long, let alone being republished in thirty or forty years' time.’
    • ‘The human landscape of Europe has changed radically over the last thirty or so years.’
    1. 1.1thirties The numbers from thirty to thirty-nine, especially the years of a century or of a person's life.
      ‘a woman in her thirties’
      ‘she was a famous actress in the thirties’
      • ‘We manage to hang on to most of it into our thirties and forties.’
      • ‘Five men, all aged in their thirties or forties, were arrested at the scene.’
      • ‘In the thirties she settled down to mystery production, and averaged nearly two novels a year.’
      • ‘We should be nurturing leadership at a much earlier age and developing skills within people in their thirties.’
      • ‘These are people who grew up in Ireland in the twenties and thirties and reached maturity in the era of World War Two.’
      • ‘Police are trying to identify the man, aged in his twenties or thirties.’
      • ‘She did not live in Ireland in the thirties; she lived in Sussex and London and merely visited Eire.’
      • ‘He was in his thirties and his death at such a young age cast a pall of sadness over the area.’
      • ‘The man, who was single and in his thirties, was on his way from Cork delivering a load of timber to a site in Waterford.’
      • ‘They are all thought to be aged in their twenties or thirties.’
      • ‘Alan introduced me to the boyish owner, a nerdy man in his early thirties.’
      • ‘When she returned New Zealand was in the grip of the Depression of the thirties with high unemployment.’
      • ‘She's a successful actor who, in her late thirties, became a successful writer.’
      • ‘He is in his late thirties or early forties and very well put together.’
      • ‘The woman was described as being aged in her thirties, with mousy brown hair cut in a bowl style and a spotty complexion.’
      • ‘Like many of the others, it is set in a suburb populated by beautiful women in their late thirties and early forties.’
      • ‘Younger women, those in their late thirties and early forties, are simply not signing up.’
      • ‘And wages vary by age - peak decades for earning are our thirties and forties.’
      • ‘A man in his late thirties, who was in the house at the time of the incident, managed to escape without injury.’
      • ‘Yeah, this record is kind of about what happens when you let your adolescence continue into your thirties.’
    2. 1.2 Thirty years old.
      ‘I've got a long way to go before I'm thirty’
      • ‘By the age of thirty he headed a household that included a wife and daughter.’
      • ‘She could have been anywhere from the age of fourteen to the age of thirty.’
      • ‘By the age of thirty, however, her siblings were unwilling to walk with her because she was so slow.’
      • ‘Men did not normally marry until between the ages of twenty-five and thirty.’
      • ‘It is a young population, with the majority under the age of thirty.’
      • ‘At the age of thirty, everything my father had told me turned out to be true.’
      • ‘She could have been any age between thirty and fifty, and was not someone to mess with.’
      • ‘At the age of thirty I was still unsure of myself and I did not even know how to spend a Sunday evening.’
      • ‘Before embarking on a political career in September 1919 at the age of thirty, Adolf Hitler had been a nonentity.’
      • ‘He was sitting alone on the other end of the couch near the mystery woman who looked around the age of thirty or so.’
      • ‘Many of the men above the age of thirty sat about a table playing a game of whist and the youngest of the children ran about the green grass of the Redford grounds.’
      • ‘While she had five children by the age of thirty, her daughters are yet to become pregnant.’
      • ‘If I could achieve my goal at the age of thirty, imagine what a 10-year-old can achieve.’
      • ‘I put it behind the desk as requested and followed the doctor, a woman roughly around the age of thirty.’
      • ‘However a university regulation prevented anyone below the age of thirty holding a chair.’
      • ‘Turning thirty, I abandoned the faux maturity and started acting as I pleased.’
      • ‘Male citizens between ages twenty-one and thirty are required to serve in the military for two years.’
      • ‘Parents over the age of thirty are becoming a larger proportion of first-time parents.’
      • ‘The average age was about thirty and a lot were travelers backpacking around the world.’
      • ‘His genius lay in the gaining and exercise of power and by the age of thirty, he acted as effective ruler of England when the King was overseas.’
    3. 1.3 Thirty miles an hour.
      ‘doing about thirty’


Old English thrītig (see three, -ty). The spelling with initial thi- is recorded in literature in the 15th century, and has been the prevalent form since the 16th century.